Unit 7 Equilibrium

Given the K_c for a forward reaction, how can you find K_c for the reverse reaction?

• Divide K_c by 1

• Divide 1 by K_c

• Square K_c

• Take the square root of K_c

For the reaction...
SO₂ + O₂  <−>  SO₃
If the concentration of SO₂ is increased, the equilibrium of the reaction will shift ___________.

• left
• right
• left and right 
• neither left nor right

Tags

NGSS.HS-PS1-5

For the reaction...

heat + N₂ + O₂ ↔ 2NO

If heat is added to the chemical system, the equilibrium will shift _______.

• left

• right

• left and right

• neither left nor right

2SO₂(g)+O₂(g)⇌2SO₃(g)

Decreasing the volume of container will

• shift equilibrium right

• shift equilibrium left

• change K

• have no change

For the reaction...
N₂  +  O₂  <=>  2NO
If  O₂ is removed, the  concentration of N₂ will _______.

• increase
• decrease
• remain the same
• double

Tags

NGSS.HS-PS1-5

The following reaction :

SO_{2 (g)} + NO_{2 (g)} <=> SO_{3 (g)} + NO (g)

had reached a state of equilibrium, was found to contain

0.40 mol L^-1 SO₃ , and 0.30 mol L^-1 NO,

0.15 mol L^-1NO₂ , and 0.20 mol L^-1 SO₂.

Calculate the equilibrium constant for this reaction.

• 4.0

• 0.42

• 0.25

• 1.0

Tags

NGSS.HS-PS1-7

What are the two factors to look for when determining if the reaction is at equilibrium?

• Forward reaction rate is faster than the reverse and concentrations are equal
• Forward and reverse reaction rates are equal and concentration is conctant
• Forward and revers reaction rates are equal and concentration is equal
• Forward reaction rate is faster than the reverse and concentration is equal

Tags

NGSS.HS-PS1-6

What is [H₂O] if K = 1.2,
[CO₂] = 0.846M, & [CH₄]= 0.0713M?
4CuO_(s)+CH_4(g)↔CO_2(g)+4Cu_(s) +2H₂O_(g)

• 0.101 M
• 0.318 M
• 0.0102 M
• 3.77 M

Tags

NGSS.HS-PS1-7

What is the correct equilibrium expression for the following reaction:
2H₂O₂(aq) ↔ 2H₂O(l) + O₂(g)

• [H₂O]²[O₂] / [H₂O₂]²
• [H₂O₂]² / [H₂O]²[O₂]
• [O₂] / [H₂O₂]²
• [H₂O]² / [H₂O₂]²

When 0.40 mole of SO₂ and 0.60 mole of O₂ are placed in an evacuated 1.00–liter flask, the reaction represented below occurs.

2SO_{2 (g)} + O_{2 (g)} ↔ 2SO_{3 (g)}

After the reactants and the product reach equilibrium and the initial temperature is restored, the flask is found to contain 0.30 mole of SO₃. Based on these results, the equilibrium constant, Kc, for the reaction is

• 20

• 10

• 6.7

• 2.0