Unit 3 (chemistry in society)

Question 1

U3-1-1

collision theory

Answer 1

for a rection to occur, reactant particles must collide with correct geometry and high enough energy

Question 2

U3-1-2

acitivated complex

Answer 2

and unstable arrangement of atoms formed at the maximum of the potential energy barrier during a reaction

Question 3

U3-1-2

activation energy

Answer 3

the minimum energy required by colliding particles to form an activated complex

Question 4

U3-2-1

molar volume

Answer 4

volume occupied by 1 mol of a gas

Question 5

U3-2-3

atom economy

Answer 5

measures the proportion of reactants that have been converted to useful products

Question 6

U3-2-4

excess reactant

Answer 6

a reactant of which we have more than the reaction requires

Question 7

U3-2-4

limiting reactant

Answer 7

a reactant which is not in excess

Question 8

U3-3-1

enthalpy

Answer 8

a measure of the chemical energy in a substance

Question 9

U3-3-2

enthalpy of combustion

Answer 9

the energy released when 1 mole of a substance undergoes complete combustion

Question 10

U3-3-3

Hess’s law

Answer 10

the enthalpy change for a chemical reaction is independent of the route taken

Question 11

U3-3-4

bond enthalpy

Answer 11

the energy required to break one mole of bonds in a diatomic molecule

Question 12

U3-3-4

mean bond enthalpy

Answer 12

the average energy required to break one mole of bonds, for a bond that occurs in a number of compounds