Question

A human patient suffering from an ulcer may show a hydrochloric acid concentration of $0.075mol/L$ in his gastric juice. It is possible to neutralize this acid with aluminium hydroxide $Al(OH{)}_3$ which reacts with $HCl$ according to the chemical reaction shown below: $[Al=27]$
$Al(OH{)}_3+HCl\to AlC{l}_3+H_{2}O$
Find the weight of $Al(OH{)}_3$ which is required to neutralize $2literHCl$.

• A. $1.95g$
• B. $6.20g$
• C. $0.693g$
• D. $3.9g$

Answer 1

The correct option is D $3.9g$

Moles of $HCl$ present in $2$ litres of gastric juice=$0.075\times 2=0.15$

Mass of $HCl$ present in $2$ litres of gastric juice=$0.15\times 36.5=5.475$ g

The balanced chemical equation is given by

$Al(OH{)}_3+3HCl\to AlC{l}_3+3H_{2}O$

According to the reaction, $109.5$ g of $HCl$ is neutralized by $78$ g $Al(OH{)}_3$

Hence, $5.475$ g $HCl$ will be neutralized by $\frac{78}{109.5}\times 5.475=3.9$ g of $Al(OH{)}_3$