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General True/False
K
Ice Tables
Calculating with K
Solving for Equilibrium/Quadratic
100

True or False: K can be either a positive or a negative value. 

False!

K can only be positive.

100

If K > 1, are products or reactants "favored"?

Products!

100

Which row's values are always positive?

Initial! (I Row)

100

Find K: A ⇌ B

[A] = 0.50 M [B] = 0.50 M


K = 1!

100

What is the quadratic formula? 

(Do you know the calculator shortcut??)

x = (-b ± √(b² - 4ac)) / (2a)

Calculator shortcut: APPS -> 9: PlySmlt2 -> 1: Polynomial Root Finder. (Order: 2, Real, Dec, Float, Degree.) -> Next -> Solve!

200

True or False: When equilibrium has been reached, the reaction has stopped.

False! 

Concentrations stop changing.

200
If equilibrium lies to the left, is K greater than or less than 1?

K<1!

200

What row determines where equilibrium goes?

Change (C Row)
200

Find K for the reaction: A + B ⇌ C

[A] = 0.20
[B] = 0.50
[C] = 0.80

K = 8.0

200

Use the quadratic formula to solve for x:

3x2 − 5x − 2 = 0

x = 2 or x = -0.3

300

True or False: Reactions can reach equilibrium from any starting conditions.

True!


300

What would the expression for the equilibrium constant be?

2A + B ⇌ 3C + D2

K= [C]3[D2] / [A]2[B]


300

Which direction would equilibrium go based on this ice table?

       A  +  B    ⇌   C

I.   1.0    1.0         0

C.  -x      -x         +x

E 1.0-x   1.0-x       x

Equilibrium went right! (Products had a +x)

300

Find K: 2A ⇌ 3B

[A] = 0.40
[B] = 0.80


K = 3.2!

300

Use the quadratic formula to solve for x:

2x2 − 7x + 3 = 0

x = 3 or x = 0.5

400

True or False: Stochiometric coefficients show up in the C row only. 

True!


400

If K is 4.53 x 10-4, are products or reactants "favored"?

Reactants!

K<1


400

Create an ICE table: A ⇌ B

Initial concentrations: It is okay for x to be unknown here

[A] = 1.0 M
[B] = 0 M

      A    ⇌    B 

 I    1.0        0

C    -x        +x

E  1.0 - x       x

400

Find K: 2A ⇌ B 

[A] = 0.50
[B] = 0.50

K = 2.0!

400

2A⇌B        K=8.0

Initial concentrations: [A]=1.00 M [B]=0

After solving the equilibrium expression, you obtain:

x=0.80 and x=0.50. Which x is correct? 

x = 0.50

500

True or False: The change in concentration for H2O (l) can be shown in an ICE table.

False!

ICE tables never include solids or liquids. 

500

What's the difference between where equilibrium lies and where equilibrium goes?

K tells you where equilibrium LIES. (K>1, K<1, K=1)

C row tells you where equilibrium GOES. The signs tell you the direction the reaction shifts.

500

Create an ICE table: N₂O₄ ⇌ 2NO₂

Initial: It is okay for x to be unknown here

[N₂O₄] = 0.574
[NO₂] = 0



    N₂O₄   ⇌     2NO₂ 

 I    0.574      0

C    -x       +2x

E  0.574 - x     2x


500

2A ⇌ B 

K = 4.0

At equilibrium: [A] = 0.50. Find [B]

B = 1.0 M!

500

Find x: N2O4  ⇌ 2NO2

Initial Concentrations: [N2O4] = 0.574. [2NO2] = 0

K = 4.65 x 10-3

x = 0.0250