Question

The zero order reaction 2N2O→2N2+O2 has the reaction constant k is 6.28×10−3 molL s. If the initial concentration of N2O is 0.962 mol/L, what is the concentration of N2O after 10.0 seconds? Your answer should have three significant figures (three decimal places).

Answer 1

Answer: The concentration of $N_2O$ in three significant figures will be 0.899 mol/L.

Explanation:

For the given reaction:

$2N_2O\rightarrow 2N_2+O_2$

The above reaction follows zero order kinetics. The rate law equation for zero order follows:

$k=\frac{1}{t}([A_o]-[A])$

where,

k = rate constant for the reaction = $6.28\times 10^{-3}\text{ mol }L^{-1}s^{-1}$

t = time taken = 10 sec

$[A_o]$ = initial concentration of the reactant = 0.962 mol/L

[A] = concentration of reactant after some time = ?

Putting values in above equation, we get:

$6.28\times 10^{-3}=\frac{1}{10}(0.962-[A])$

$[A]=0.899mol/L$

Hence, the concentration of $N_2O$ in three significant figures will be 0.899 mol/L.