Consider the gaseous reaction, $$ A_2+B_2 \longrightarrow 2 A B $$ The following data was obtained for the above reaction.

[A₂]₀	[B₂]₀	Initial rate of formation of AB (mol L⁻¹ s⁻¹)
0.1 M	0.1 M	2.5 × 10⁻⁴
0.2 M	0.1 M	5.0 × 10⁻⁴
0.2 M	0.1 M	1.0 × 10⁻³

The value of rate constant for the above reaction is

Adsorption of a gas a solid adsorbent follows. Freundlich adsorption isotherm. If $x$ is the mass of the gas adsorbed on mass ' $m$ ' of the adsorbent at pressure $p$. From the graph given extent of adsorption is proportional to

Consider the following reactions.

$$ X+\mathrm{O}_2 \rightarrow \mathrm{Cu}_2 \mathrm{O}+\mathrm{SO}_2, \mathrm{Cu}_2 \mathrm{O}+X \rightarrow \mathrm{Cu}+Y \uparrow $$

The shape of the molecule $Y$ is

$Y$ in the given sequence of reactions is

$$ \begin{gathered} \mathrm{P}_4+x \mathrm{NaOH}+y \mathrm{H}_2 \mathrm{O} \xrightarrow{\mathrm{CO}_2} X+z \mathrm{NaH}_2 \mathrm{PO}_2 \\ X+\mathrm{CuSO}_4 \longrightarrow Y+\mathrm{H}_2 \mathrm{SO}_4 \end{gathered} $$