A flask is filled with gas A. Gas A reacts to form gas B: 2 A(g) B(g). The parti
ID: 876289 • Letter: A
Question
A flask is filled with gas A. Gas A reacts to form gas B: 2 A(g) B(g). The partial pressure of gas A is measured over time and given in the table. Rate = = k. The first data point was collected 10 minutes after reaction begins.
Look at the data carefully to determine the order of reaction for gas A. Give your reasoning below.
Find the rate constant for this reaction.
Calculate the pressure of gas A at t = 200 min.
Determine the pressure of the product gas B at t = 200 min.
t
-10
0
40
80
120
200
PA
-
0.224
0.112
0.075
0.056
?
PB
0
-
-
-
-
?
t
-10
0
40
80
120
200
PA
-
0.224
0.112
0.075
0.056
?
PB
0
-
-
-
-
?
Explanation / Answer
To determine the order, let's assume an order to determinate k. If it's order 1:
LnP = -kt + LnPo
Ln (P/Po) = -kt
Ln (Po/P) / t = k
k1 = ln(0.224/0.112) / 40 = 0.017329
k2 = ln(0.112/0.075) / 40 = 0.010025
k3 = ln(0.075/0.056) / 40 = 0.0073
The values of K are all differents, so the reaction should be of order 2:
1/P - 1/Po = kt
k1 = (1/0.112 - 1/0.224) / 40 = 0.1116
k2 = (1/0.075 - 1/0.112) / 40 = 0.1101
k3 = (1/0.056 - 1/0.075) / 40 = 0.1131
The reaction is order 2 -----> k = 0.1116 min-1
1/P(200) = (1/0.056) + (0.1116x80)
P = 0.037
To determine the pressure of B:
2A = B
i) 2x 0
ii) 2x - y y
The innitial pressure was 0.224 and the final was 0.037. We know that the total pressure is:
Pt = Pa + Pb so
0.037 = 2(0.224 - y) + y
0.037 = 0.448 -2y + y
y = 0.411 = Pb
Related Questions
drjack9650@gmail.com
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.