reaction rates

Question 1

_________- in chemistry, the speed at which a chemical reaction proceeds.

Answer 1

Reaction rate

Question 2

It is often expressed in terms of either the concentration (amount per unit volume) of a product that is formed in a unit of time or the concentration of a reactant that is consumed in a unit of time.

Answer 2

Reaction rate

Question 3

This theory says that atoms, ions, and molecules can form a chemical bond when they collide, provided the particles have enough kinetic energy. Particles lacking the necessary kinetic energy to react still collide, but simply bounce.

Answer 3

Collision theory

Question 4

The minimum energy colliding particles must have in order to react is the _________.

Answer 4

activation energy

Question 5

it is a barrier that the reactants must cross to be converted to products.

Answer 5

activation energy

Question 6

T or F. Molecules must collide with the proper orientation.

Answer 6

True

Question 7

A collision that meets the two criteria, and that results in a chemical reaction, is known as a ________ or ________

Answer 7

successful collision or an effective collision.

Question 8

T or F. Molecules must collide before they can react

Answer 8

True

Question 9

raising the temperature speeds up a reaction. Lowering the temperature usually slows reactions down.

Answer 9

Effect of Temperature

Question 10

At higher temperatures the motions of the reactant particles are more chaotic and more energetic than at lower temperatures.

Answer 10

Effect of Temperature

Question 11

The number of reacting particles in a given volume affects the rate at which reactions occur. Cramming more particles into a fixed volume increases the collision frequency.

Answer 11

Effect of Concentration

Question 12

T or F. Increasing the concentration of reactants decreases the reaction rate.

Answer 12

False

Question 13

The total surface area of a solid or liquid reactant has an important effect on the reaction rate. The smaller the particle size, the larger the surface area for a given mass of particles.

Answer 13

Effect of Particle Size

Question 14

T or F. An increase in surface area increases the collision frequency and the reaction rate.

Answer 14

True

Question 15

T or F. An increase in temperature is not always the best way to increase the rate of a reaction. A catalyst, if one can be found, is often better.

Answer 15

True

Question 16

A _______ is a substance that increases the rate of a reaction without being used up itself in the reaction.

Answer 16

catalyst

Question 17

_________permit reactions to proceed at a lower energy than is normally required.

Answer 17

Catalysts

Question 18

An _________ is a substance that interferes with the action of a catalyst.

Answer 18

inhibitor

Question 19

_______________ naturally favor the formation of products at the specified conditions.

Answer 19

Spontaneous reactions