Consider the following reaction in a closed reaction flask. If 1.50 atm of gas A
ID: 794817 • Letter: C
Question
Consider the following reaction in a closed reaction flask. If 1.50 atm of gas A is allowed to react with 0.500 atm of gas B and the reaction goes to completion at constant temperature and volume, what is the total pressure in the reaction flask at the end of the reaction? What are the partial pressures of the gases in the flask?
4A(g) + 6B(g) ? 2A2B3(g)
A. (1.00 atm of A3B produced) + (0.333 atm of A remaining) = 1.33 atm total pressure
B. (0.667 atm of A3B produced) + (0.333 atm of B remaining) = 1.00 atm total pressure
C. (0.333 atm of A3B produced) + (0.167 atm of A remaining) = 0.500 atm total pressure
D. (0.333 atm of A3B produced) + (0.667 atm of B remaining) = 1.00 atm total pressure
Explanation / Answer
Reaction occurs at constant T and V.
Using pV = nRT , we see that n is directly proportional to pressure.
4A + 6B ---> 2A2B3
we can see that gas B is limited.
6 parts of B reacts with 4 parts of A to form 2 parts of A2B3
0.5 atm of B reacts with 0.333 atm of A to form 0.166 atm A2B3
B is totally consumed.
Remaining PP of A = 1.5 - 0.333 = 1.167 atm
PP of A2B3 = 0.166 atm
Total Pressure = 1.333 atm