OZONE STORY - OCR B A-LEVEL CHEMISTRY.

what is electronegativity

is a measure of the ability of an atom to attract electrons in a chemical bond to itself

explain the qualitative trends of electronegativity in the periodic table

use of relative electronegativity values to predict bond polarity in a covalent bond;

relation of overall polarity of a molecule to its shape and the polarity of its individual bonds

what is an instantaneous dipole-induced dipole?

when an instantaneous dipole induces a dipole disturbing the electron arrangement in the non polar species.

explain dependence on branching and chain length of organic molecules and Mr)

what is the weakest type of intermolecular bonding

instantaneous dipole-induced dipole

what is permanent dipole-permanent dipole?

a permanent dipole is polar e.g hydrogen chloride. H-CL - H-CL, this is a permanent dipole-permanent dipole bond. stronger than instantaneous dipole-induced dipole bonding.

describe the formation of hydrogen bonds

hydrogen bonding in ice

hydrogen bonding in water

describe the boiling points of the halogens

what is activation enthalpy

the minimum amount of kinetic energy needed between two particles before a reaction will occur

what is an enthalpy profile

useful for picturing what energy changes are happening throughout the reaction, the highest point on the pathway corresponds to the transition state.

The effect of concentration and pressure on the rate of a reaction explained in terms of the collision theory

use of the concept of activation enthalpy and the Boltzmann distribution to explain the qualitative effect of temperature changes and catalysts on rate of reaction; techniques and procedures for experiments in reaction kinetics including plotting graphs to follow the course of a reaction

the role of catalysts in providing alternative routes of lower activation enthalpy

what is a homogenous catalyst

describe the formation of intermediates

calculations, from given data, of values for composition by volume of a component in a gas mixture measured in percentage concentration and in parts per million (ppm)