What is the percentage by mass of oxygen in NaOH ? (Atomic mass of $\mathrm{Na}=23 \mathrm{u}, \mathrm{O}=16 \mathrm{u}, \mathrm{H}=1 \mathrm{u}$ )

For the reaction

$$\begin{aligned} & 2 \mathrm{NO}_{(\mathrm{s})}+2 \mathrm{H}_{2(\mathrm{~g})} \longrightarrow \mathrm{N}_{2(\mathrm{~g})}+2 \mathrm{H}_2 \mathrm{O}_{(\mathrm{s})} \\\\ & \text { rate }=\mathrm{k}[\mathrm{NO}]^2\left[\mathrm{H}_2\right] . \end{aligned}$$

What is the order of reaction with respect to $\mathrm{H}_2$ and overall order of reaction respectively?

Identify the alloy used for construction of gas turbine engines.

Calculate the partial pressure exerted by dioxygen from a mixture of $32 \mathrm{~g} \mathrm{O}_2, 80 \mathrm{~g} \mathrm{Ar}$ (mol.mass 40 ) and 4 g dihydrogen $\left(\mathrm{P}_{\text {total }}=10 \mathrm{bar}\right)$.