## ICE BOX and coefficients

Dakota_Campbell_1C
Posts: 51
Joined: Fri Sep 28, 2018 12:15 am

### ICE BOX and coefficients

When doing ice box problems what are you supposed to do with the coefficient in front of a molecule? do you add it to the change or do you multiply? Also when you are adding Mols to the equation do you change it for the base equation?

Josephine Lu 4L
Posts: 62
Joined: Fri Sep 28, 2018 12:18 am

### Re: ICE BOX and coefficients

the coefficient in front of the molecule is multiplied to x when you fill out the change values in the ICE box. For example, if a molecule has the coefficient 2, it would change by +/- 2x.

Julia Go 2L
Posts: 60
Joined: Sun Sep 30, 2018 12:17 am
Been upvoted: 1 time

### Re: ICE BOX and coefficients

Using the equation N2(g) + 3H2(g) <--> 2NH3(g) as an example. The coefficients in front of the reactant and product affects the change in concentration. If you started with 0.1M of N2 and H2, in the ICE box you would put the initial concentration as:

N2 = 0.1
H2 = 0.1
NH3 = 0

Next for the change in concentration, it would be:

N2 = -x
H2 = -3x
NH3 = +2x

Finally the equilibrium concentration is:

N2 = 0.1-x
H2 = 0.1-3x
NH3 = 2x

Selina Bellin 2B
Posts: 62
Joined: Fri Sep 28, 2018 12:25 am

### Re: ICE BOX and coefficients

if you have a coefficient in ur reaction, in the ICE box, multiply ur equilibrium (for example, x) by the coefficient. also, don't forget in ur K expression to use that coefficient as its exponent

Michelle Song 1G
Posts: 30
Joined: Wed Nov 14, 2018 12:23 am

### Re: ICE BOX and coefficients

When there are coefficients in front of the molecules you multiply it by x (the change).