Unit#5: Reaction Kinetics

1

Reaction rate can be measured by:

A Color change B Mass change C Gas volume D All of these

2

Which graph best represents a fast reaction?

A Gentle slope B Horizontal line C Steep slope D Zigzag line

3

Which graph shows effect of catalyst?

A Higher activation energy B Lower activation energy C Same activation energy D No energy change

4

What is meant by the rate of a chemical reaction?

A Amount of catalyst used B Time taken for completion C Change in concentration per unit time D Temperature of reaction

5

Enzymes are best described as:

A Inorganic catalysts B Synthetic chemicals C Biological catalysts D Reactants

6

Which process in food industry uses enzymes?

A Rusting B Fermentation C Combustion D Electrolysis

7

Chemical kinetics helps in food preservation by:

A Speeding up spoilage B Slowing down reactions C Changing nutrients D Adding colors

8

For a collision to be effective, particles must have:

A Large size B Same color C Sufficient energy D High density

9

Which factor has no effect on enzyme activity?

A pH B Temperature C Substrate concentration D Color of enzyme

10

Which reaction condition increases enzyme efficiency?

A Extreme pH B Optimal temperature C High pressure D Low substrate

11

Chemical kinetics helps the food industry mainly by:

A Improving taste B Controlling reaction speed C Changing color D Increasing weight

12

Enzyme-substrate complex is formed during:

A Physical change B Chemical reaction C Diffusion D Evaporation

13

Which factor is least important for solid-solid reactions?

A Surface area B Temperature C Concentration D Catalyst

14

Pressure mainly affects reactions involving:

A Solids B Liquids C Gases D Solutions

15

Enzymes are mainly made of:

A Carbohydrates B Proteins C Fats D Minerals

16

Milk turning into yogurt is an example of:

A Physical change B Enzyme catalyzed reaction C Diffusion D Evaporation

17

Increasing concentration increases reaction rate because:

A Particles become larger B More collisions occur C Activation energy increases D Temperature increases

18

A catalyst increases reaction rate by:

A Increasing activation energy B Decreasing activation energy C Being consumed D Changing products

19

Increasing surface area of reactants will:

A Decrease reaction rate B Not affect reaction rate C Increase reaction rate D Stop the reaction

20

Collision theory applies mainly to reactions in:

A Solid state B Gaseous state C Plasma state D Vacuum

21

Fast reactions usually have:

A High activation energy B Low activation energy C No collisions D Low temperature

22

Food spoilage can be slowed by lowering:

A Pressure B Temperature C Volume D Mass

23

Diffusion occurs fastest in:

A Solids B Liquids C Gases D Plasma

24

In collision theory, proper orientation means:

A Particles must collide head-on B Particles must be parallel C Particles must collide randomly D Particles must have same mass

25

Enzymes are specific because:

A They work for all reactions B They work for specific substrates C They are inorganic D They are consumed