In: Chemistry
The decomposition of SO2Cl2 is first order in SO2Cl2 and has a rate constant of 1.38×10−4 s−1 at a certain temperature.
What is the half-life for this reaction?
How long will it take for the concentration of SO2Cl2 to decrease to 25% of its initial concentration? Express your answer using two significant figures.
If the initial concentration of SO2Cl2 is 1.00 M, how long will it take for the concentration to decrease to 0.72 M ? Express your answer using two significant figures.
If the initial concentration of SO2Cl2 is 0.125 M , what is the concentration of SO2Cl2 after 220 s ?
If the initial concentration of SO2Cl2 is 0.125 M , what is the concentration of SO2Cl2 after 550 s ?
1) The decomposition of SO2Cl2 is first order in SO2Cl2 and has a rate constant of 1.38×10?4 s?1 at a certain temperature.
What is the half-life for this reaction?
Solution: half life = t1/2 = 0.693 / K = 0.693 / 1.38×10?4 s?1 = 5021.7 seconds
2) How long will it take for the concentration of SO2Cl2 to decrease to 25% of its initial concentration? Express your answer using two significant figures.
Solution: the time required will be = two half lives = 5021.7 + 5021.7 = 10043.4 seconds
The same can also be solved as
ln [A]/ [At] = kt
ln [100/25] = 1.38×10?4 s?1 X time
time = 10045.6 seconds
3) If the initial concentration of SO2Cl2 is 1.00 M, how long will it take for the concentration to decrease to 0.72 M ? solution:
ln [A]/ [At] = kt
ln [1/0.72] = 1.38×10?4 s?1 X time
time = 2380.43 seconds
4) If the initial concentration of SO2Cl2 is 0.125 M , what is the concentration of SO2Cl2 after 220 s ?
Solution:
ln [A]/ [At] = kt
ln [0.125 / At] = 1.38×10?4 s?1 X 220
[0.125 / At] = 1.031
[At] = 0.121 M
5) If the initial concentration of SO2Cl2 is 0.125 M , what is the concentration of SO2Cl2 after 550 s ?
Solution:
ln [0.125]/ [At] = kt
ln [0.125 / At] = 1.38×10?4 s?1 X 550
0.125 / At = 1.0789
At = 0.116 M