Question

Match the plots given in List I with their slopes given in List II and select the correct answer using the code given below the lists :

List I	List II
P. c $ \upsilon s $ t (abscissa) for zero order reaction	1.Unity
Q. log c $ \upsilon s $ t (abscissa) for first order reaction	2. Zero
R. $\left(-\frac{d c}{d t}\right) \upsilon s C$ for Zero order reaction	3. $-k$
S.ln $\left(-\frac{d c}{d t}\right)$ $\upsilon s$ ln C for first order reaction	4. $-\frac{k}{2.303}$

first order reaction
$\begin{matrix}P&Q&R&S\end{matrix}$

• A. $\begin{matrix}4&3&2&1\end{matrix}$
• B. $\begin{matrix}3&4&2&1\end{matrix}$
• C. $\begin{matrix}2&4&3&1\end{matrix}$
• D. $\begin{matrix}3&2&4&1\end{matrix}$

Answer 1

Answer: (B)

(P) For a zero order reaction, $C=C_{0}-kt$
(Q) For a first order reaction , log C=$log C_{0}-\frac{k}{2.303} \times t$
(R) For a zero order reaction, $-\frac{d c}{d t}=k $ (constant)
Hence, slope of $-\frac{d c}{d t} \nu s C=0$
(S) For a first order reaction, $-\frac{d c}{d t} =kc,$
ln $\left(-\frac{d c}{d t}\right)=ln k+ln C.$
Hence, plot of ln $\left(-\frac{d c}{d t}\right)$ against ln C will have slope equal to unity.