Question

$50mL$ of $1M$ oxalic acid is shaken with $0.5g$ of wood charcoal. The final concentration of the solution after adsorption is $0.5M$. What is the amount of oxalic acid adsorbed per gram of carbon?

• A. $3.15$
• B. $1.575$
• C. $6.30$
• D. $12.60$

Answer 1

The correct option is C $6.30$

Weight of 50 mL of 1 M oxalic acid

$Molarity=\frac{m}{M\times Vol.ofsol\left(L\right)}$ (m=mass)

$1=\frac{m\times 100}{126\times 50}$

$m=\frac{126\times 50\times 1}{1000}=6.3g$

Wt of 50 ml of 0.5 M oxalic acid

$=\frac{0.5\times 126\times 50}{1000}=3.15g$

Amount of oxalic acid absorbed on 0.5 g charcoal

$=6.3-3.15=3.15g$

Amount of oxalic acid absorbed on 1 gram or per gram charcoal

$=3.15\times 2=6.3g$