Question

What are neutral oxides? Explain the nature of zinc oxide with the help of reactions. Define 'Molar Conductivity' and 'Zero order reaction'.
In a first order reaction $x\to y$, $40$% of the given sample of compound remains unreacted in $45$ minutes. Calculate rate constant of the reaction.

Answer 1

The oxides which are neither acidic nor basic are called as neutral oxides. Ex. $NO$, $CO$, $N_{2}O$ etc.
Amphoteric nature of $ZnO$
$Zn{O}_{\left(s\right)}+2H{Cl}_{\left(aq\right)}⟶Zn{Cl}_{2\left(s\right)}+H_2{O}_{\left(l\right)}$
$Zn{O}_{\left(s\right)}+2NaO{H}_{\left(aq\right)}⟶{Na}_{2}Zn{O}_{2\left(aq\right)}+H_2{O}_{\left(l\right)}$
Molar conductivity : The conductance of a volume of a solution containing $1$ mole of dissolved electrolyte when placed between two parallel electrode $1cm$ apart.
Zero orderreaction : The reaction whose rate is independent of the reaction concentration and remain constant throughout the course of the reaction.
Solution :
At $t=45$ min; Initial concentration ${\left[A\right]}_o=100$, final concentration ${\left[A\right]}_t=40$
$K=\frac{2.303}{t}{\log }_{10}\frac{{\left[A\right]}_o}{{\left[A\right]}_t}$
$=\frac{2.303}{45}{\log }_{10}\frac{100}{40}$
$=\frac{2.303}{45}{\log }_{10}2.5$
$=\frac{2.303\times 0.3979}{45}$
$=0.02036{min}^{-1}$