Question

$1g$ of activated charcoal at STP undergoes monolayer of adsorption of $N{H}_3$. If $1g$ of charcoal has surface area of $2\times 10^2{m}^2$ and effective surface area of $N{H}_3$ molecule is $0.17n{m}^2$, the millimoles of $N{H}_3$ adsorbed on $20g$ of charcoal is _____ .
$\left[N_A=6.0\times 10^{23}mo{l}^{-1}\right]$

Answer 1

Answer: 39.17

Surface area of charcoal available for adsorption
$=20\times 2\times 10^2{m}^2=4\times 10^3{m}^2$
Effective surface area of $1N{H}_3$ molecule
$=0.17n{m}^2$
$0.17\times (10^{-9}{)}^2=0.17\times 10^{-18}{m}^2$
Number of molecules of $N{H}_3$ adsorbed
$=\frac{4\times 10^3}{0.17\times 10^{-18}}=2.35\times 10^{22}$ molecules
Amount of $N{H}_3$ adsorbed $=\frac{2.35\times 10^{22}}{6.0\times 10^{23}}$
$=0.03917mol$
$39.17mmol$