Advertisements
Advertisements
प्रश्न
The following data were obtained during the first order thermal decomposition of SO2Cl2 at a constant volume.
\[\ce{SO2Cl2_{(g)} -> SO2_{(g)} + Cl2_{(g)}}\]
| Experiment | Time/s–1 | Total pressure/atm |
| 1 | 0 | 0.5 |
| 2 | 100 | 0.6 |
Calculate the rate of the reaction when total pressure is 0.65 atm.
Advertisements
उत्तर १
The thermal decomposition of SO2Cl2 at a constant volume is represented by the following equation.
\[\ce{SO2Cl2_{(g)} -> SO2_{(g)} + Cl2_{(g)}}\]
| At t = 0 | P0 | 0 | 0 |
| At t = t | P0 − p | p | p |
After time t,
Total pressure (Pt) = (P0 − p) + p + p
⇒ Pt = (P0 + p)
⇒ p = Pt − P0
∴ P0 − p = P0 − (Pt − P0)
= 2 P0 − Pt
For a first-order reaction,
k = `2.303/t log P_0/(P_0 - p)`
When t = 100 s,
k = `2.303/(100 s)log 0.5/(2 xx 0.5 - 0.6)`
When Pt = 0.65 atm,
P0 + p = 0.65
⇒ p = 0.65 − P0
= 0.65 − 0.5
= 0.15 atm
∴ When the total pressure is 0.65 atm,
Pressure of SOCl2 \[\ce{(P_{SO_2Cl_2})}\] = P0 − p
= 0.5 − 0.15
= 0.35 atm
∴ The rate of equation, when total pressure is 0.65 atm, is given by,
Rate = \[\ce{k(P_{SO_2Cl_2})}\]
= (2.23 × 10−3 s−1) × (0.35 atm)
= 7.8 × 10−4 atm s−1
उत्तर २
Given: P0 = 0.5 atm,
Pt (at t = 100 s) = 0.6 atm
If P0 is the initial pressure and Pt at time t, we have,
k = `2.303/t log_10 P_0/(2P_0 - P_t)`
= `2.303/100 log_10 0.5/(2 xx 0.5 - 0.6)`
= 2.2318 × 10−3 s−1
When Pt = 0.65 atm, i.e.,
P0 + x = 0.65
∴ x = 0.65 − P0
= 0.65 − 0.5
x = 0.15 atm
Pressure of SO2Cl2 when the total pressure is 0.65 atm, i.e.,
\[\ce{P_{SO_2Cl_2}}\] = P0 − x
= 0.50 − 0.15
= 0.35 atm
∴ The required rate of reaction = k × \[\ce{P_{SO_2Cl_2}}\]
= 2.2318 × 10−3 × 0.35
= 7.81 × 10−4 atm s−1
संबंधित प्रश्न
In a pseudo first order reaction in water, the following results were obtained:
| t/s | 0 | 30 | 60 | 90 |
| [A]/mol L−1 | 0.55 | 0.31 | 0.17 | 0.085 |
Calculate the average rate of reaction between the time interval 30 to 60 seconds.
The time required for 10% completion of a first order reaction at 298 K is equal to that required for its 25% completion at 308 K. If the value of A is 4 × 1010 s−1. Calculate k at 318 K and Ea.
A first order reaction takes 20 minutes for 25% decomposition. Calculate the time when 75% of the reaction will be completed.
(Given : log = 2 = 0·3010, log 3 = 0·4771, log 4 = 0·6021)
A first order reaction is 50% completed in 1.26 × 1014 s. How much time would it take for 100% completion?
With the help of an example explain what is meant by pseudo first order reaction.
A first order reaction is 50% complete in 20 minute What is rate constant?
In a first order reaction the concentration of reactants decreases from 400mol L-1 to 25 mol L-1 in 200 seconds. The rate constant for the reaction is ______.
Observe the graph shown in figure and answer the following questions:

- What is the order of the reaction?
- What is the slope of the curve?
- Write the relationship between k and t1/2 (half life period).
Gaseous cyclobutene isomerizes to butadiene in a first order process which has a 'k' value of 3.3 × 10−4 s−1 at 153°C. The time in minutes it takes for the isomerization to proceed 40% to completion at this temperature is ______. (Rounded-off to the nearest integer)
The decomposition of formic acid on gold surface follows first-order kinetics. If the rate constant at 300 K is 1.0 × 10−3 s−1 and the activation energy Ea = 11.488 kJ mol−1, the rate constant at 200 K is ______ × 10−5 s−1. (Round off to the Nearest Integer)
(Given R = 8.314 J mol−1 K−1)
A definite volume of H2O2 undergoing spontaneous decomposition required 22.8 c.c. of standard permanganate solution for titration. After 10 and 20 minutes respectively the volumes of permanganate required were 13.8 and 8.25 c.c. The time required for the decomposition to be half completed is ______ min.
The reaction \[\ce{SO2Cl2(g) -> SO2(g) + Cl2(g)}\] is a first-order gas reaction with k = 2.2 × 10−5 sec−1 at 320°C. The percentage of SO2Cl2 is decomposed on heating this gas for 90 min, is ______%.
The slope in the plot of `log ["R"]_0/(["R"])` Vs. time for a first-order reaction is ______.
How will you represent first order reactions graphically?
What is the rate constant?
The following data were obtained during the decomposition of SO2Cl2 at the constant volume. SO2Cl2 →SO2(g) + Cl2(g)
| Time (s) | Total Pressure (bar) |
| 0 | 0.5 |
| 100 | 0.6 |
Calculate the rate constant of the reaction.
Write the equation for integrated rate law for a first order reaction.
Write the unit of rate constant [k] for the first order reaction.
If the half-life (t1/2) for a first order reaction is 1 minute, then the time required for 99.9% completion of the reaction is closest to ______.
