G10 Unit 28 Catalysts and Catalyzed Reactions

Question 1

a substance that increases the reaction rate without being consumed by the reaction

Answer 1

catalyst

Question 2

It provides a new pathway for the reaction, one that has lower activation energy. This is a process known as

Answer 2

catalysis

Question 3

The catalyzed reaction has _ activation energy or energy barrier.

Answer 3

lower

Question 4

When there is less energy required for a reaction to proceed, then the reacting molecules will form the products in _ time.

Answer 4

less

Question 5

Kinds of Catalysis

Answer 5

heterogeneous catalysis

homogeneous catalysis.

Question 6

The phases of the catalyst and the reactants differ in _ catalysis

Answer 6

heterogeneous catalysis

Question 7

heterogeneous catalysis which is a way of producing nitric acid

Answer 7

Ostwald process

Question 8

a type of heterogeneous catalysis is the use of_ _in automotives

Answer 8

catalytic converters

Question 9

_ catalysis involves the catalyst and the reactants being in the same phase.

Answer 9

Homogeneous

Question 10

The formation of acetic acid from water and ethyl acetate is one such example, but this process is slow without the use of a catalyst.

The catalyst in this case is usually some type of acid, which speeds up acetic acid formation.

Question 11

This is an example of anacid-base catalysis, which is one of the more notable types of homogeneous catalysis.

Question 12

More frequent collisions and lower energy required will naturally lead to a faster chemical reaction.

What most catalysts do is lower the activation energy.

Question 13

The Process of Catalysis/Steps of Catalysis

Answer 13

Bonding
Reaction
Separation

Question 14

The catalyst forms a bond with the reacting molecules

Answer 14

Bonding

Question 15

The reacting molecules combine or rearrange to form the product.

Answer 15

Reaction

Question 16

The product separates from the catalyst.

Answer 16

Separation

Question 17

Hydrogen peroxide in aqueous solution undergoes decomposition into water and oxygen:2H2O2(l)→2H2O(l)+O2(g)2H2O2(l)→2H2O(l)+O2(g)

Iodine can be used to catalyze this decomposition reaction.

Iodine usually exists as diatomic moleculeI2I2. However, in aqueous solution, it tends to split into two iodine anions.

Question 18

of Catalysis

If iodine is involved, you can rewrite the above equation in two ways:

Catalyst on top of the arrow:2H2O2(l)I2→2H2O(l)+O2(g)2H2O2(l)→I22H2O(l)+O2(g)

Catalyst as both reactant and product:2H2O2(l)+I2(s)→2H2O(l)+O2(g)+I2(s)

Question 19

The mechanism of the catalyzed reaction occurs in three steps:

Bonding - The iodine cation forms a bond with one oxygen molecule. Note that one of the products, water, is already formed.H2O2(aq)+I+(aq)→H2O(l)+OI−(aq)H2O2(aq)+I+(aq)→H2O(l)+OI−(aq)

Reaction – TheOI–OI–anion reacts with some of the remaining hydrogen peroxide molecules to form water and oxygen.H2O2(aq)+OI−(aq)→H2O(l)+O2(g)+I+(aq)H2O2(aq)+OI−(aq)→H2O(l)+O2(g)+I+(aq)

Separation – TheI+I+reappeared on the product side. It has separated from the oxygen it previously bonded. It is free again to react with the remainingH2O2H2O2molecules.