Chemistry - All Definitions

  • Created by: jklos5899
  • Created on: 16-10-19 10:47
How close to the true value a measurement is
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A chemical that is a proton donor and releases H+ ions in aqueous solutions
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Activation Energy
The minimum energy required to start a reaction by breaking bonds in the reactants
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Identifies the purpose of the investigation
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A group of organic compound where the parent group is -OH
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Alicyclic Hydrocarbon
A hydrocarbon with carbon atoms joined together in a ring structure
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A chemical that reacts with an acid and is soluble in water releasing hydroxide ions
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A homologous series of saturated hydrocarbons
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A homologous series of unsaturated hydrocarbons
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Amount of Substance
The quantity whose unit is the mole.
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Amphoteric Substances
Substances that can react both as acids and bases
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Aliphatic Hydrocarbon
A hydrocarbon where carbon atoms are joined together in straight or branched chains
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A substance that contains no water molecules
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A negatively charged ion
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Data points that do not fit the overall trend in the data
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Results that do not follow the general pattern of the data
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A solution in which the solvent is water. Shown as (aq)
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Aromatic Hydrocarbons
Contain at least one benzene ring
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The smallest object that retains the properties of an element. Composed of electrons and a nucleus.
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Atomic (Proton) Number
The number of protons in the nucleus of an atom
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Atomic Orbital
A region of space where it is likely you will find electrons. Each orbital can hold up to two electrons, with opposite spins
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Atomic Radius
A measure of the size of an atom.
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Atomic Structure
Consists of a positively charged nucleus surrounded by negatively charged electrons revolving in orbits at varying distances from the nucleus. The constitution of the nucleus and arrangement of electrons varies with elements. An atom has zero charge
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Average Bond Enthalpy
The mean energy needed for 1 mole of a given type of gaseous atoms to undergo homolytic fission
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Avogadro Constant
The number of atoms per mole of the carbon-12 isotope
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A chemical that can react with acids and is a proton acceptor
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Biodegradable Materials
Are affected by the action of microorganisms and environmental conditions leading to decomposition
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Biological Catalysts
Catalysts found in nature are called enzymes and help catalyse reactions in the body
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Materials made from a renewable source that are biodegradable
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Boltzmann Distribution
The distribution of energies of molecules at a particular temperature, often shown as a graph
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Bond Angle
The angle that is formed between two adjacent bonds on the same atom
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Bonded Pair
A pair of electrons that have been shared between two chemically bonded atoms
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Bonding Region
The space where an electron can be found in a bond
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An organic molecule that contains the C=O functional group
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Carboxylic Acids
An organic acid containing a carboxyl functional group -COOH
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The quantitative study of energy change in a chemical reaction
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A substance that increases the rate of a reaction without being used up during the process
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Categoric Variable
A qualitative description of a variable
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A positively charged ion
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Chlorofluorocarbons are a class of organic compounds which contain carbon and fluorine. They are inert and non toxic to humans.
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Chemical Energy
A special form of potential energy stored in chemical bonds
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cis-trans Isomerism
A type of E/Z isomerism where two substituent groups attached to each carbon atom of the C=C group are the same
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Collision Theory
A model to help understand and make predictions about how changing temperature, pressure, concentration, surface area or catalyst may change the rate of a reaction.
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Complete Combustion
The oxidising of a fuel in a plentiful supply of air
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A substance formed from two or more chemically bonded elements in a fixed ratio, usually shown by a chemical formula
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Concentration of a Formula
The amount of solute, in mol, dissolved per 1 dm (1000 cm ) of solution
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Concordant Results
Vaules that are close to each other and therefore represent reliable quantitative data
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Continuous Variable
A measured value which could be any number
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Control Variable
A factor that you must keep constant between experimental runs so that you can compare results
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Covalent Bond
A bond formed by a shared pair of electrons between nuclei
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Curly Arrows
Model the flow of electron pairs during reaction mechanisms
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A region within the atom that can hold up to two electrons, with opposite spins
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Dative Covalent Bond
A bond formed by a shared pair of electrons that has been provided by one of the bonding atoms only. Also known as a coordinate bond
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A chemicl reaction where water molecules are eliminated from an organic compound
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Delocalised Electrons
Electrons that are shared between more than two atoms
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Delta Negative
Slight negative charge
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Delta Positive
Slight positive charge
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Dependent Variable
The factor you observe in an experiment
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Diatomic Molecules
Molecules composed of only two atoms, of either the same or different elements
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The process of decreasing the concentration of a solute in solution, usually by mixing with more solvent
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Discrete Variables
Variables that can only be particularly defined by numbers
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Displacement Reaction
A reaction in which a more-reactive element takes the place of a less-reactive element in a compound
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Displayed Formula
A formula which shows the relative positioning of atoms and the bonds between them
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The oxidation and reduction of the same element in a redox reaction
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A technique used to separate miscible liquids or solutions
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Dot-and-Cross Diagrams
Used to model the electrons in chemical bonding
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Dot Formulae
Gives the ratio between the number of compound molecules and the number of water molecules within the crystalline structure
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Dynamic Equilibrium
The equilibrium that exists in a closed system when the rate of the forward reaction is equal to the rate of the reverse reaction and all chemicals have their concentrations maintained
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E/Z Isomerism
A type of stereoisomerism that is caused by the restricted rotation around the double bond. Two different groups are attached to each carbon atom of the C=C bond.
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Electrical Conductivity
The degree to which a specified material allows charge to be carried.
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The smallest of the particles that make up an atom, and carry a negative charge. The number of protons and electrons is equal in every atom
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Electron Configuration
The arrangement of electrons in an atom or ion
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Electron Shielding
The repulsion between electrons in different inner shells. Shielding reduces the net attractive force from the positive nucleus on the outer shell electrons
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A measure of the attraction of an electron in a covalent bond
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An electron-pair acceptor
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A substance that cannot be broken down into simpler substances chemically. Composed of atoms that have the same atomic number.
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An organic chemical reaction in which one reactant forms two products. Usually a small molecule like water is released.
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Empirical Formula
The simplest whole number ratio of atoms of each element present in a compound
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A reaction in which the enthalpy of the products is greater than the reaction of the reactants, resulting in heat being taken in from the surroundings
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The heat content that is stored in a chemical reaction
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Enthalpy Change of Combustion
The energy change that takes place when 1 mole of a substance is completely combusted
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Enthalpy Change of Formation
The energy change that takes place when 1 mole of a compound is formed from its constituent elements in their standard state under standard conditions
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Enthalpy Change of Neutralisation
The energy change associated with the formation of 1 mole of water from a neutralisation reaction, under standard conditions
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Enthalpy Change of Reaction
The energy change associated with a given reaction
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Enthalpy Cycle
A pictorial representation showing alternative routes between reactants and products
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Enthalpy Profile Diagram
A diagram of a reaction thatallows you to compare the enthalpy of the reactants with the enthalpy of the products
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Equilibrium Constant
The equilibrium constant gives a measure of where the equilibrium lays, essentially by giving the ratio between products and reactants
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A functional group of COO found in some organic molecules
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The chemical reaction which forms an ester
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A reaction in which the enthalpy of the products is less than the enthalpy of the reactants, resulting in heat loss to the surroundings
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An ordered set of practical steps, which are used to test a hypothesis
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Extraneous Variable
A factor that is not controlled or measured in an experiment but may introduce errors into results
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False Positive
When a positive result is produced but not due to the desired product being formed
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First Ionisation Energy
The energy required to remove one electron from each atom in one mole of gaseous atoms to form one mole of gaseous 1+ atoms
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The process in mass spectrometry that causes a positive ion to split into pieces, one of which is a positive fragment ion
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Functional Group
A group of atoms that is responsible for the characteristic chemical reactions of a compound
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General Formula
The simplest algebraic formula for a homologous series
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Giant Covalent Lattice
A 3-D structure of atoms that are all bonded together by strong covalent bonds
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Giant Ionic Lattice
A 3-D structure of oppositely charged ions, held together by strong electrostatic forces of attraction
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Giant Metallic Lattice
A 3-D structure of positive ions and delocalised electrons, bonded together by strong metallic bonds
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Global Warming
The increased average temperature of the planet and atmosphere, though to be caused by increased concentrations of CO2
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The measure of a slope on a graph. Choose two points on a graph and divide change in y-axis by change in x-axis
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A vertical column in the periodic table. Elements in a group have similar chemical properties and their atoms have the same number of outer-shell electrons
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An addition reaction where a halogen is added across the C=C
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A group of chemical compounds derived from alkanes containing one or more halogens.
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Hess' Law
States that the enthalpy change in a chemical reaction is independent of the route it takes
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Heterogenous Catalysts
A catalyst used in a reaction which is in a different phase than the reactant
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Heterolytic Fission
Happens when each bonding atom receives one electron from the bonded pair, forming two radicals
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Homogeneous Catalysts
A catalyst used in a reaction which is in the same phase as the reactant
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Homologous Series
A series of organic compounds that have the same functional group with successive members differing by CH
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Homolytic Fission
Happens when one bonding atom receives both electrons from the bonding pair
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A crystalline compound containing water molecules
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A reaction where water is a reactant in a chemical reaction
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Compounds that contain only hydrogen and carbon atoms only
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Hydrogen Bond
A strong permanent dipole-permanent dipole attraction between an electron-deficient hydrogen atom on one molecule, and a lone pair of electrons on a highly electronegative atom on a different molecule
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An addition reaction where hydrogen is added across the C=C
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A chemical reaction in which water is a reactant. There are alkali hydrolysis reactions where -OH is the reacting species
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A prediction and explanation of the chemistry behind the prediction
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Incomplete Combustion
Oxidising a fuel in a limited supply of air
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Independent Variable
The factor that you are interested in changing to see the effect it has on one other factor
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Refers to the region of the EM spectrum with wavelengths between 700 nm and 300 micrometers. Between microwaves and visible light
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Infrared Spectroscopy
An analytical technique that utilises a substances behaviour of absorbing infrared radiation and produces a spectrum that can only be used to identify certain functional groups.
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Intermolecular force
An attractive force between neighbouring molecules or atoms
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A positively or negatively charged atom or covalently bonded group of atoms
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Ionic Bond
The electrostatic attraction between oppositely charged ions
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The process of an atom becoming an ion
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Atoms of the same element with a different number of neutrons
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A measurement of energy where 1 kJ = 1000 J
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Law of Conservation of Energy
Energy cannot be created or destroyed, only moved from one place to another
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Le Chatelier's Principle
When a system is in dynamic equilibrium is subjected to a change, the position of equilibrium will shift to minimise the change
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Line of Best Fit
Shows the trend in plotted points - this could be a straight line, curve or any shape
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London (dispersion) Forces
Attractive forces between induced dipoles in neighbouring molecules
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Lone Pair
An outer-shell pair of electrons that is not involved in chemical bonding
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Margin of Error
Shows the range a value lies in
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Mass Number
The number of particles (protons and neutrons) in the nucleus
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Mass Spectrometry
An analytical chemistry technique that helps identify the amount of types of chemicals present in a sample by measuring the mass-to-charge ratio and abundance of gas-phase ions
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Metallic Bonding
The electrostatic attraction between positive metal ions (cations) and delocalised electrons
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Meta-Study and Meta-Analysis
A type of secondary research using raw data from a variety of studies and using it to try and answer the new aim
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A step-by-step detailed explanation of how to complete an experiment
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Molar Gas Volume
The volume per mole of a gas
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Molar Mass
The mass per mole of a substance
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Molar Volume
The volume per mole of a gas
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The amount of any substance containing as many particles as there are carbon atoms in exactly 12 g of the carbon-12 isotope
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Molecular Formula
Shows the number and types of atoms of each element in a compound
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Molecular Ion
The positive ion formed in mass spectrometry when a molecule loses an ion
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A group of atoms held together by covalent bonds
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Small molecules that are used to make polymers
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Multiple Covalent Bond
Some non-metallic atoms can share more than one pair of electrons with another atom to form a multiple bond. e.g. a double or triple bond
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The reaction of an acid with a base
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A particle found in the nucleus of an atom. It is almost identical in mass to a proton, but carries no electric charge
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The naming system for compounds
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Particles found in the nucleus of an atom. (Protons and Neutrons)
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Electron pair donors
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Nucleophilic Substitution
A chemical reaction in which an atom or group of atoms is exchanged for a nucleophile
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Organic Synthesis
A branch of chemistry which designs reactions to make a target molecule
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A summary of the experiment
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The loss of electrons, the loss of hydrogen, gain of oxygen or an increase in oxidation number
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Oxidising Agent
A reagent that oxidises another species
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Ozone Layer
An area of high concentration of ozone in the stratosphere
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A region within an atom that can hold up to two electrons, with opposite spins
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Particle Model
A simplification of matter which can be used to explain observations and make predictions
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Percentage Error
A mathematical way of comparing the experimental value with the actual value
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Percentage Yield
Actual amount, in mol, of product / theoretical amount, in mol, of product x 100
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A horizontal row of elements in the periodic table. Elements show trends in properties across a period
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Periodic Table
A tabular arrangement of the chemical elements, organised on the basis of their atomic number, electron configurations, and recurring chemical properties
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A regular periodic variation of properties of elements with atomic number and position in the Periodic Table
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Permanent Dipole
A small charge difference across a bond that results from a difference in the electronegativities of the bonded atoms
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Permanent dipole-dipole Interaction
A weak attractive force between permanent dipoles and permanent or induced dipoles in neighbouring polar molecules
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Capable of being decomposed by the action of light, especially sunlight
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pi Bonds
Sideways overlap of adjacent p-orbitals above and below the bonding C atoms
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A summary of the experiment that you wish to complete
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Polar Covalent Bond
A covalent bond that has a permanent dipole
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A macromolecules made from small repeating units (monomers)
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Precipitation Reaction
The formation of a solid from a solution during a chemical reaction. Precipitates are often formed when two aqueous solutions are mixed together
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The degree to which repeated values, collected under the same conditions in an experiment, show the same results
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A measure of the force applied over a unit area
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Primary Alcohol
Has the functional group attached to a carbon atom with no more than one alkyl group
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Primary Haloalkane
Has the halogen on the end of the parent chain
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Principal Quantum Number
A number representing the relative overall energy of each orbital, which increases with the distance from the nucleus. The sets of orbitals with the same value are referred to as electron shells
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Substances made/formed in a chemical reaction
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Particle found in the nucleus with a positive charge. The number of these gives the atomic number.
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Qualitative Data
A description of what is being observed
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Qualitative Test
A simple test where an observation can be used to identify a species
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Quantitative Data
A quantity of what is being observed
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A selection of heat resistant glassware with connectors that can be easily put in a variety of arrangements
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A highly reactive species with one or more unpaired electrons
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The emission of energy as electromagnetic waves or as moving subatomic particles, especially high-energy particles which cause ionisation.
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Radical Substitutions
An organic mechanism involving radicals where one or more atoms get exchanged
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Rate of Reaction
The change in concentration of a reaction or a product in a given time
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A substance that takes part in and undergoes change during a reaction
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Reaction Mechanism
Models which show clearly the movement of electron pairs in a reaction
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Collecting, sorting and processing of waste for a different use
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The purification of a liquid using multiple distillations
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Redox Reaction
A reaction in which both reduction and oxidation take place
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Reducing Agent
A reagent that reduces (adds electrons to) another species
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The gain of electrons, gain of hydrogen, loss of oxygen or a decrease in oxidation number
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A technique used to stop reaction mixtures boiling away into the air
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Relative Atomic Mass
The weighted mean mass of an atom of an isotope compared with one-twelfth of the mass of an atom of carbon-12
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Relative Isotopic Mass
The mass of an atom of an isotope compared with one-twelfth of the mass of an atom of carbon-12
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Results that are similar when they are repeated
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Repeating Unit
A specific arrangement of atoms that occurs in the structure over and over again.
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The smallest change in quantity being measured that can be observed
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A spherical shaped region within an atom that can hold up to two electrons with opposite spins.
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Any chemical compound formed from an acid when an H+ ion from the acid has been replaced by a metal ion or another positive ion, often a metal or ammonium ion.
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Saturated Compounds
Compounds that have only single bonds
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Saturated Organic Compounds
Organic chemicals that have only one single covalent bond
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The degree or extent to which a species is dissolved or absorbed compared with the maximum possible, usually expressed as a percentage
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Scatter Graphs
A method for expressing quantitative data, where the independent variable must be continuous and on the x-axis. The dependent variable must be continuous and on the y-axis.
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Secondary Alcohol
Has the functional group attached to a carbon atom with two alkyl groups
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Separating Funnel
A piece of equipment used to separate immiscible liquids
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A group of atomic orbitals with the same principal quantum number.
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Sigma Bonds
Made by direct overlap between orbitals on the bonding atoms
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Significant Figures
The numbers used to represent a quantity that have meaning
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Single Covalent Bonds
Where atoms are bonded by one shared pair of electrons between nuclei
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Simple Molecular Lattice
A three-dimensional structure of molecules held together by weak intermolecular forces
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Skeletal Formula
A simplified structural formula drawn by removing hydrogen atoms from alkyl chains
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The property of a solid, liquid or gas called a solute to to dissolve in a solid, liquid or gaseous solvent to form a homogeneous solution of the solute in the solvent
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Any type of particle that takes place in a chemical reaction
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Specific Heat Capacity
The energy required to raise 1 g of a substance by 1 K
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Standard Condition
Standard sets of conditions for experimental measurments established to allow comparisons to be made between data. Set at 100 kPa, 298 K
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Standard Form
Method for writing very small or large numbers
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Standard Solution
A solution of known concentration. Normally used in titrations to determine unknown information about another substance
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Organic compounds with the same molecular formula and structural formula but having different arrangement of atoms in space
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The molar relationship between the relative quantities of substances taking part in a reaction
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Structural Formula
Provides the minimum detail to show the arrangement of atoms in a molecule
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Structural Isomers
Compounds with the same molecular formula but with different structural formula
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A group of the same type of atomic orbitals within a shell. 's' subshells hold a maximum of two electrons, 'p' hold six and 'd' hold ten.
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Successive Ionisation
Values that are a measure of the energy required to remove each electron in turn
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A type of primary research. It is setting out limits to observe something that is already happening
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Chemical processes which minimise the use and generation of hazardous materials
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Synthetic Polymers
Human-made polymers
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A clear and structured way of recording information about an experiment
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Tertiary Alcohol
Has the functional group attached to a carbon atom with three alkyl groups
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A branch of physical chemistry concerned with changes in the energy of chemical systems and surroundings
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The slow addition of one solution of a known concentration to a known volume to a known volume of another a solution of unknown concentration until the reaction reaches an end point.
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Unsaturated Organic Chemicals (Compounds)
Organic chemicals that contain at least one carbon-carbon double covalent bond
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Valid Experiment
Provides information to test the aim of the experiment
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Van der Waals' Forces
A type of intermolecular bonding that includes permanent dipole-dipole bonding and induced dipole-dipole interactions (London Forces)
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Factors that can affect the outcome of an experiment
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The tendency of a substance to vaporize
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The quantity of three-dimensional space occupied by a liquid, solid, or gas.
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Water of Crystallisation
Water molecules that form an essential part of the crystalline structure of a compound
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Weighing by Difference
A method used to accurately weigh the amount of material transferred. The mass of a container before and after transferring the material is taken and the difference between these values is the mass of material transferred
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The amount of product obtained in a chemical reaction
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Addition Polymer
A very long molecular chain formed by repeated addition reactions of many unsaturated alkene molecules (alkenes)
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Addition Reaction
A reaction in which a reactant is added to an unsaturated molecule to make a saturated molecule
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Aliphatic Hydrocarbon
A hydrocarbon where carbon atoms are joined together in straight or branched chains
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Alkylammonium Salt
A compound where the hydrogen on an ammonium ion have been substituted by alkyl chains
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Addition of hydrocarbon chains to an organic compound
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Alkyl Group
An alkane with a hydrogen atom removed. Often shown as 'R'
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A class of compound with a functional group made of an acyl group, which is directly attached to an amine
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A naturally occurring aromatic compound, which is a very stable planar ring structure with delocalised electrons
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Benzene Derivative
A benzene ring that has undergone a substitution reaction
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Bronsted-Lowry Acid
A proton donor
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Bronsted-Lowry Base
A proton acceptor
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Buffer Solution
A mixture that minimises pH changes on addition of small amounts of acid or base.
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An organic ion in which a carbon atom has a positive charge
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Chemical Shift
The scale that compares the frequency of NMR absorption with the frequency of the reference peak of TMS
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Chiral Carbon
A chiral carbon has four different groups attached to it
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A visible record showing the result of separation of the components of a mixture by chromatography
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Complex Ion
A transition metal ion bonded to one or more ligands by coordinate bonds
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Condensation Polymerisation
The chemical reaction to form a long-chain molecule by elimination of a small molecule, such as water
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Conjugate Acid-Base Pair
Two species that transform into each other by gain or loss of a proton
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Coordination Number
The total number of coordinate bonds formed between a central metal ion and its ligands
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Degradable Polymer
A polymer that breaks down into smaller fragments when exposed to light, heat or moisture
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An isotope of hydrogen and does not produce a signal in the NMR Spectrum
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Directing Effect
How a functional group directly attached to an aromatic ring affects which carbon atoms are more likely to undergo substitution
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Electrophilic Substitution
A substitution reaction where an electrophile is attracted to an electron-rich atom or part of a molecule and a new covalent bond is formed by the electrophile accepting an electron pair
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An optical isomer
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End Point
The point in a titration at which there are equal concentrations of the weak acid and conjugate base forms of the indicator. The colour at the end point is midway between the colours of the acid and conjugate base forms
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The quantitative measure of the degree of disorder in a system
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Equivalence Point
The point in a titration at which the volume of one solution has reacted exactly with the volume of the second solution. This matches the stoichiometry of the reaction taking place
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Equivalent Carbon Atoms
Carbon atoms bonded to the same atom, which therefore experience the same magnetic field in the NMR spectrometer
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Equivalent Protons
Hydrogen atoms bonded to the same atoms that therefore experience the same magnetic field in the NMR spectrometer
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First Electron Affinity
The enthalpy change accompanying the formation of 1 mole of gaseous 1- ions from gaseous atoms
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Friedel-Crafts Reaction
A substitution reaction where hydrogen is exchanged for an alkyl, or acyl chain. Friedel-Crafts reactions allow electrophilic substitution to occur on an aromatic ring
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Geometric Isomers
Molecules that have the same structural formula but a different arrangement in space
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The time taken for the concentration of a reactant to reduce by half
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Heterogeneous Equilibrium
An equilibrium in which species making up the reactants and products are in different physical states
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Homogeneous Equilibrium
An equilibrium in which all the species making up the reactants and products are in the same physical state
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A species formed in one step of a multi-step reaction that is used up in a subsequent step, and is not seen as either a reactant or product of the overall equation
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Isoelectric Point
The pH value at which the amino acid exists as a zwitterion
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Lattice Enthalpy
The enthalpy change that accompanies the formation of one mole of an ionic lattice from its gaseous ions under standard conditions
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Lewis Acid
An electron-pair acceptor
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A molecule or ion that can donate a pair of electrons to the transition metal ion to form a coordinate bond
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Ligand Substitution
A reaction in which one ligand in a complex ion is replaced by another ligand
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Mobile Phase
The phase that moves in chromatography
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A simplified version that allows us to make predictions and understand observations more easily
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Mole Fraction
A measure of how much of a given substance is present in a reaction mixture
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An organic chemical with a -CN functional group
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A species that contains a lone pair of electrons or a negative charge and is attracted to positive areas of a molecule
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Optical Isomers
Molecules which are non-superimposable mirror images of each other. They have the same chemical properties but interact with polarised light differently
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With respect to a reactant, the order is the power to which the concentration of the reactant is raised in the rate equation
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Overall Order
The overall order of a reaction is the sum of the individual orders, m + n
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Oxidation Number
A measure of the number of electrons that an atom uses to bond with atoms of another element. Oxidation numbers are derived from a set of rules
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Partial Pressure
The pressure an individual gaseous substance would exert if it occupied a whole reaction vessel on its own
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A physically distinctive form of a substance
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A class of aromatic compounds where a hydroxyl group is directly attached to the aromatic ring
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Polar Molecule
A molecule with an overall dipole, having taken into account any dipoles across bonds
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Precipitation Reaction
The formation of a solid from a solution during a chemical reaction. Precipitates are often formed when two aqueous solutions are mixed together
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Qualitative Analysis
An observable change and does not involve observations using numerical values
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Rate Constant (k)
The constant that links the rate of reaction with the concentrations of the reactants raised to the powers of their orders in the rate equation
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Rate-Determining Step
The slowest step in the reaction mechanism of a multi-step reaction
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A method for purifying organic compounds
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Relative Molecular Mass
The weighted mean mass of a molecule of a compound compared with one-twelfth of the mass of an atom of carbon-12
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Retention Time
The time taken for a component to travel from the inlet to the detector in a gas chromatogram
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Where the synthetic route is designed by looking at the target molecule and working backwards
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Rf Value
A comparison between how far a component has moved compared to the solvent in thin layer chromatography
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Saturated Hydrocarbon
A hydrocarbon with single bonds only
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Second Electron Affinity
The enthalpy change accompanying the formation of 1 mole of gaseous 2- ions from 1 mole of gaseous 1- ions
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Spectator Ions
Ions that are present but that play no part in a chemical reaction
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Spin-Spin Coupling
The interaction between spin states of non-equivalent nuclei that results in a group of peaks in an NMR spectrum
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Standard Electrode Potential of a Half Cell
The e.m.f. of a half cell compared with a standard hydrogen half-cell, measured at 298 K with solution concentration of 1 mol dm and a gas pressure of 100 kPa
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Standard Enthalpy Change of Atomisation
The enthalpy change that accompanies the formation of 1 mole of gaseous atoms from the element in its standard state
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Standard Enthalpy Change of Hydration
The enthalpy change that takes place when dissolving 1 mol of gaseous ions in water
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Standard Enthalpy Change of Solution
The enthalpy change that takes place when one mole of solute is completely dissolved in water under standard conditions
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Standard Entropy
The entropy content of one mole of a substance under standard conditions
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Standard Entropy Change of Reaction
The entropy change that accompanies a reaction in the molar quantities expressed in a chemical equation under standard conditions, all reactants and products being in their standard states
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Stationary Phase
The phase that does not move in chromatography
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The longest carbon chain present in an organic molecule
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Substitution Reaction
When an atom or group of atoms is replaced by a different atom or group of atoms
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Synthetic Route (Synthetic Pathway)
A series of reactions that can be used to change a starting chemical into a target molecule
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An internal standard carbon and proton NMR
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Transition Metal
A d-block element that has an incomplete d-subshell as a stable ion
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Unsaturated Hydrocarbon
A hydrocarbon containing multiple carbon-to-carbon bonds
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Weak Acid
An acid that partially dissociates in solution
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An internal salt, with no charge, formed by the donation of a proton from a carboxylic acid functional group to the amine functional group in an amino acid
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Other cards in this set

Card 2


A chemical that is a proton donor and releases H+ ions in aqueous solutions



Card 3


The minimum energy required to start a reaction by breaking bonds in the reactants


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Card 4


Identifies the purpose of the investigation


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Card 5


A group of organic compound where the parent group is -OH


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