Question

For a chemical reaction $A⟶B$, it was found that concentration of $B$ is increased by $0.2{\text{mol L}}^{-1}$ in 30 min. The average rate of the reaction is ____$x\times {10}^{-1}{\text{mol L}}^{-1}{h}^{-1}$. The value of x (in nearest integer)

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• A. 4.0
• B. 4
• C. 4.00

Answer 1

Answer: (A), (B), (C)

$A\to B$

$\text{Average rate}=\frac{\text{Increase in concentration of B}}{\text{Time}}$

$r_{avg}=\frac{0.2{\text{mol}}^{-1}}{0.5hr}$

$r_{avg}=0.4=4\times {10}^{-1}{\text{mol L}}^{-1}{h}^{-1}x=4$