Question 4.20: For the decomposition of azoisopropane to hexane and nitrogen at 543 K, the following data are obtained.
Calculate the rate constant.
Answer
Let initial pressure = po
And pressure after time t = pt
Amount of substance = a
Decomposed quantity = x
The decomposition of azoisopropane to hexane and nitrogen at 543 K is
In this problem we take pressure in place of concentration or quantity
Final pressure due to reactant = po - p = 2po - pt
Plug the values from the table we get
When t = 360 sec
k1 = 2.175 × 10−3 s−1
When t = 720 sec
K2= 2.235 × 10−3 sec−1
Hence, the average value of rate constant is
To get average value add both values and divide by 2 we get
k = (k1 +k2)/2
After calculation we get
k= 2.21 × 10−3 sec−1
Calculate the rate constant.
Answer
Let initial pressure = po
And pressure after time t = pt
Amount of substance = a
Decomposed quantity = x
The decomposition of azoisopropane to hexane and nitrogen at 543 K is
In this problem we take pressure in place of concentration or quantity
Final pressure due to reactant = po - p = 2po - pt
Plug the values from the table we get
When t = 360 sec
k1 = 2.175 × 10−3 s−1
When t = 720 sec
K2= 2.235 × 10−3 sec−1
Hence, the average value of rate constant is
To get average value add both values and divide by 2 we get
k = (k1 +k2)/2
After calculation we get
k= 2.21 × 10−3 sec−1
