Q26 / 160 · TS EAMCET 2020 (11 Sep Shift 2) · Chemistry
What is the unit for the zero order rate constant?
- Correct answerA$\mathrm{L}^{-1} \mathrm{~mol} \mathrm{~s}^{-1}$
- B$\mathrm{L} \mathrm{mol} \mathrm{s}^{-1}$
- C$\mathrm{L} \mathrm{mol}^{-1} \mathrm{~s}^{-1}$
- D$\mathrm{L}^2 \mathrm{~mol}^{-2} \mathrm{~s}^{-1}$
Solution
$\because$ Rate $(r)=$ rate constant $(k)$ [conc. $]^{\text {order }}$
$k=\frac{\text { rate }}{[\text { conc. }]^{\text {order }(=n)}}=\frac{\mathrm{mol} \mathrm{L}^{-1}}{\left[\mathrm{~mol} \mathrm{~L}^{-1}\right]^n}$
where, $n=$ order of reaction
$\therefore \quad k=\mathrm{mol}^{1-n}, \mathrm{~L}^{n-1} \mathrm{~s}^{-1}$
For zero order $(n=0)$
$\therefore \quad k=\mathrm{mol} \mathrm{L}^{-1} \mathrm{~s}^{-1}$
Hence, the correct answer is option: 'A'.