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Flashcards in 17 - 4 Deck (19):
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What is rxn rate?

How fast a reaction happens

1

How is rxn rate measured?

TRIANGLE [reactant]/unit time

2

How can rxn rate be determined?

Experiment

3

What is one thing rxn rate determines?

How fast a cake bakes

4

What influences rxn rate?

Nature of the reactions & surface area, T, [. ], & catalyst

5

Define nature of the reactants

Ionic(reacts instantly) or covalent (May take hours)

6

Describe what happens when T increases

Increased T will increase KE which will increase the # of particles with enough energy to "go" WRT E-act

7

Describe what happens when [ ] increases

Will increase KE cuz there are more particles preset to collide

8

Define catalysts

Substances that increase the rate of a rxn without being involved in rxn

9

How do catalysts work?

By decreasing e-Act

10

When will a catalyst be homogenous?

WRT reactants (of the same phase)

11

When will catalysts be heterogeneous?

WRT reactants (different phases)

12

What's the opposite of a catalyst?

Inhibitor

13

What is an inhibitor also known as?

Preservative

14

Define preservative

Stops or slows a rxn by forming stable, nonreactive intermediate species w/ reactants, keeping to busy to react

15

Define rate laws

Mathematical expressions that relate the rate of a rxn to the [ ]'s of thee reactants

16

How do you write a rate law?

1.) Keep [ ] of reactants constant & time it
2.) vary the [ ] of one & time it again
3.) vary the [ ] of the other & time it again

17

When is rxn rate 1st order?

Double-double
Triple-triple

18

When is rxn rate 2nd order?

Double-quadruple
Triple- 9 fold