Module 1 - F325

Question 1

Rate of reaction

Answer 1

Rate of reaction is the change in concentration of a reactant or product per unit time.

Question 2

Initial rate of reaction

Answer 2

Initial rate of reaction is the change in concentration of a reactant, or product, per unit time at the start of the reaction when t=o.

Question 3

Rate equation

Answer 3

A + B —> C is given by rate =k[A]m [B]n.
m is the order of reaction with respect to A
n s the order of reaction with respect to B

Question 4

Order

Answer 4

The order with respect to a reactant is the power to which the concentration of the reactant is raised in the rate equation.

Question 5

Overall Order

Answer 5

The overall order of reaction is the sum of the individual orders, m+n

Question 6

Rate constant, K

Answer 6

The rate constant, K, is 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.

Question 7

Half-life

Answer 7

The half-life of a reactant is the time taken for the concentration of the reactant to reduce by half.

Question 8

Reaction Mechanism

Answer 8

A reaction mechanism is a series of steps that, together, make up the overall reaction.

Question 9

Rate-determining step

Answer 9

The rate-determining step is the slowest step in the reaction mechanism of a multi-step reaction.

Question 10

Intermediate

Answer 10

An intermediate is a species fromed 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 a product of the overall equation.

Question 11

Dynamic Equilibrium

Answer 11

Dynamic equilibrium exists in a closed system when the rate of the forward reaction is equal to the rate of the reverse reaction.

Question 12

Homogeneous equilibrium

Answer 12

A homogeneous equilibrium is an equilibrium in which all the species making up the reactants and products are in the same physical state.

Question 13

Heterogeneous equilibrium

Answer 13

A heterogeneous equilibrium is an equilibrium in which species making up the reactants and products are in different physical states.

Question 14

Bronsted- Lowry acid

Answer 14

A bronsted lowry acid is a proton, H+, donor.

Question 15

Bronsted- Lowry base

Answer 15

A bronsted lowry base is a proton, H+, acceptor.

Question 16

Alkali

Answer 16

An alkali is a base that dissolves in water forming OH- ions.

Question 17

Neutralisation

Answer 17

Neutralisation is a chemical reaction in which an acid and a base react together to produce a salt and water.

Question 18

Acid-base pair

Answer 18

An acid-base pair is a pair of two species that transform into each other by gain or loss of a proton.

Question 19

Strong acid

Answer 19

A strong acid is an acid that completely dissociates in solution.

Question 20

Weak acid

Answer 20

A weak acid is an acid that partially dissociates in solution.

Question 21

Buffer Solution

Answer 21

A buffer solution is a mixture that minimizes pH changes on addition of small amounts of acid or base.

Question 22

Equivalence point

Answer 22

The equivalence point is the point in a titration at which the volume of one solution has reacted exactly with the volume of the second solution.

Question 23

End point

Answer 23

The end point is the point in a titration at which there are equal concentrations of the weak acid and conjugate base forms of the indicator.

Question 24

Standard enthalpy change of neutralisation

Answer 24

Standard enthalpy change of neutralization is the energy change that accompanies the neutralization of an aqueous acid by an aqueous base to form one mole of water, under standard conditions.