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Flashcards in Unit 5 Deck (23)
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1

What is an equilibrium?

A dynamic condition in which the forward rate of a process equals the reverse rate in a closed system

2

What is equilibrium shown by? What does this mean?

It is shown by a double headed arrow
It means the process occurs in both directions

3

What does it mean if the forward reaction is favoured in an equilibrium reaction?

It means the forward reaction is nearly complete before the reverse reaction establishes equilibrium
Higher concentration of products than reactants at equilibrium

4

What does it mean if the reverse reaction is favoured in an equilibrium reaction?

It means the forward reaction is just starting when the reverse reaction establishes equilibrium.
There is a higher concentration of reactants than products at equilibrium

5

How do we analyze a graph of equilibrium reactants and products to see which is favoured?

Products start at zero and go up while reactants start at a higher number and go down.
Which ever line is higher than the other is where the reaction is favoured

6

What is Le Châtelier's principle?

States that when an equilibrium is stressed, it will shift to relieve the stress since they are dynamic

7

How do you calculate the movement of a reaction when the pressure is increased?

Count the number of mols of gas on each side, then the equation will shift to whichever side has less mols of gas

8

If pressure is increased or decreased, and the number of mols of gas are the same on both sides where does the equation shift?

No change.

9

Which states of elements don't affect an equilibrium?

Liquids (l) or solids (s)

10

What is an endothermic reaction?

Where the energy (heat) is on the reactant side (left side)

11

What is an exothermic reaction?

Where the energy (heat) is on the product side (right)

12

What is the Keq equation?

Keq= products/reactants
Coefficients of compounds are used as exponents
Ex: aA + bB >< cC + dD
Keq= (C^c)(D^d) / (A^a)(B^b)

13

What states of elements are not included in the Keq?

Liquids (l) and solids (s)

14

If Keq is greater than one (>1) what is favoured?

Products are favoured (more products around at equilibrium)

15

If Keq is less than 1 (<1) what is favoured?

Reactants are favoured (more reactants around at equilibrium)

16

If Keq is equal to one (=1) what is favoured?

None. Reactants and products are equal concentration at equilibrium

17

Does changing the pressure, concentration, or adding a catalyst affect the Keq?

No

18

For an endothermic reaction, how does the temperature affect the Keq?

When the temperature goes up, the Keq goes up
When the temperature goes down, the Keq goes down

Parallel

19

For an exothermic reaction, how does the temperature affect the Keq?

When the temperature goes up, the Keq goes down
When the temperature goes down, the Keq goes up

Inverse

20

When reactants are converted into products, their concentrations ___________ and the concentrations of the products ___________

Decrease
Increase

21

What would a homogenous reaction mean?

All gases or all aqueous, etc

22

What would a heterozygous reaction mean?

Some gas some aqueous, etc

23

Reactions tend to run to completion if a product is ________

Is precipitated as a solid