Step 6: Plug the value for xinto the expression of the equilibrium concentration for NO.
[NO]= 2 x= 2(1.50)= 3.00 M
Note:You could also solve this problemusing equilibrium partial pressures of the gases:
K.
PP
P 400
p NONO
22
2
==
^^hh
Use P = CRT, where C represents the molar concentration of the gas, vn
Try this approach to confirm that [NO] = 3.00 M.
- Solid carbon reacts with carbon dioxide gas to produce carbon monoxide. At 1,500°C,
the reaction is found to be at equilibrium with a Kpvalue of 0.50 and a total pressure of
3.5 atm. What is the proper expression for the partial pressure (in atmospheres) of the
carbon dioxide?
A.
...
21
-+ 05 0502 - -4 1 35
^
^^^
h
8 hhhB
B.
...
21
-+ 05 0502 - -4 1 175
^
^^^
h
8 hhhB
C.
...
21
-+ 05 050 4 1- - 175
^
^^^
h
8 hhhB
D.
...
21
-+ 05 0502 - 2 1 35
^
^^^
h
8 hhhB
E.
...
21
05 +-- 0502 4 1 175
^
^^^
h
8 hhhB
Answer: B
Step 1: Write the balanced equilibrium equation.
C(s) + CO 2 (g) ↔2 CO(g)
Step 2: Write the equilibrium expression.
P.
P
p^050
CO
CO^2
2
K==
^h
Step 3: Express the two unknowns, pressure of CO and pressure of CO 2 , in terms of a single
unknown, pressure of CO.
Ptotal= PCO+ PCO 2 = 3.5 atm
PCO 2 = 3.5 atm −PCO
Equilibrium