The reaction of iodomethane with sodium ethoxide proceeds as : $Et{O}^{⊝}+MeI\to EtOMe+<mspace\; width="1em"></mspace>I^{⊝}$

A plot of log $\left\{\frac{\left[MeI\right]}{\left[Et{O}^{⊝}\right]}\right\}$on the Y-axis against 't' on the X-axis gives a straight line with a positive slope. What is the order of the reaction ?

(1) Second                                                

(2) First

(3) Third                                                   

(4) Fractional

For the reaction, C₂H₅I + OH^- → C₂H₅OH + I^- the rate constant was found to have a value of 5.03 × 10^-2 moI^-1 dm³ s^-1 at 289 K and 6.71 mol^-1 dm³ s^-1 at 333 K. 

The rate constant at 305 K will be: 

$1.$ $1.35$ $mo{l}^{-1}$ $d{m}^3$ $s^{-1}$                  

$2.$ $0.35$ $mo{l}^{-1}$ $d{m}^3$ $s^{-1}$

$3.$ $3.15$ $mo{l}^{-1}$ $d{m}^3$ $s^{-1}$                    

$4.$ $7.14$ $mo{l}^{-1}$ $d{m}^3$ $s^{-1}$

A plot of ln rate Vs ln C for the nth order reaction gives 

(1) a straight line with slope n and intercept ln $k_n$

(2) a straight line with slope (n – 1)

(3) a straight line with slope ln $k_n$ and intercept ‘n’

(4) a straight line with slope –n and intercept $k_n$

The rate constant of a first-order reaction increases from 1.667 × 10⁻⁶ s⁻¹ at 727 °C to 1.667 × 10⁻⁴ s⁻¹ at 1571 °C. Assuming that the activation energy remains constant, calculate the rate constant at 1150 °C.

The solvolysis of 2-chloro-2-methyl propane in aqueous acetone: $H_{2}O+{\left(C{H}_3\right)}_{3}C-Cl\to HO-C{\left(C{H}_3\right)}_3+H^{+}C{l}^{-}$ has a rate equation. 

Rate =$K\left[\right(C{H}_3<mspace\; width="1em"></mspace>{)}_3<mspace\; width="1em"></mspace>C<mspace\; width="1em"></mspace>–<mspace\; width="1em"></mspace>Cl].$From this it may be inferred that the energy profile of the reaction leading from reactants to products is

(A)                                 

(B) 

(C)                             

(D) 

The thermal decomposition of a compound is of first order. If 50 % of a sample of the compound decomposes in 120 minutes, how long will it take for 90 % of the compound to decompose?

1. 399 min                                                        

2. 410 min

3. 250 min                                                        

4. 120 min

The half-life for radioactive decay of ${}^{14}C$ is 5730 y. An archaeological artifact containing wood had only 80 % of the ${}^{14}C$ found in a living tree. The age of the sample will be:

1. 1657.3 y                                                

2. 1845.4 y

3. 1512.4 y                                                

4. 1413.1 y

Calculate the time after which the concentrations of substances A and B become equal if [A₀] = 4[B₀]. Both undergo first-order decay with half-lives of 5 min and 15 min, respectively.

1.  15 minutes                                        

2.  10 minutes

3.  5 minutes                                          

4.  12 minutes

The following data were obtained during the first-order thermal decomposition of $S{O}_{2}C{l}_2$ at a constant volume.

SO₂Cl₂(g) → SO₂(g) + Cl₂(g)

The rate of the reaction when total pressure is 0.65 atm will be:

1. $7.8$ $\times$ ${10}^{-4}$ $s^{-1}$ $atm.$                                  

2. $0.8$ $\times$ ${10}^{-4}$ $s^{-1}$ $atm.$

3. $2.4$ $\times$ ${10}^{-2}$ $s^{-1}$ $atm.$                                   

4. $6.1$ $\times$ ${10}^{-8}$ $s^{-1}$ $atm.$

Assertion : A lump of coal burns at a moderate rate in air while coal dust burns explosively.

Reason : Coal dust contains very fine particles of carbon.