Definitions H

Question 1

Hess’ law

Answer 1

If a reaction can take place by more than one route and the initial and final conditions are the same, the total entropy change is the same for each route

Question 2

Heterogeneous catalysis

Answer 2

A reaction in which the catalyst has a different physical state from the reactants; frequently reactants are gases whilst the catalyst is a solid

Question 3

Heterolytic fission

Answer 3

Breaking of a covalent bond forming a cation (positive ion) and anion (negative ion)

Question 4

Homogeneous catalyst

Answer 4

A reaction in which the catalyst and the reactants are in the same physical state, which is frequently the aqueous or gaseous state

Question 5

Homologous series

Answer 5

A series of organic compounds with the same functional group but with each successive member differing by CH2

Question 6

Homolytic fission

Answer 6

The breaking of a covalent bonds with one of the bonded electrons going to each atom, forming to radicals

Question 7

Hydrated

Answer 7

A crystalline compound containing water molecules.

Question 8

Hydrocarbon

Answer 8

A compound containing carbon and hydrogen only

Question 9

Hydrogen bond

Answer 9

A strong dipole dipole attraction between an electron deficient hydrogen atom of NF, OH or HF on one molecule and a lone pair of electrons on a highly electronegative atom containing N, O or F on a different molecule

Question 10

Hydrolysis

Answer 10

A reaction with water that breaks a chemical bond into two compounds the H and OH in a water molecule becomes incorporated into the two compounds