Question

$1.25g$ of a solid dibasic acid is completely neutralised by $25ml$ of $0.25$ molar $Ba(OH{)}_2$ solution. Then calculate the molecular mass of the acid.

Answer 1

Solution:-

As we know that,

$M=\frac{W_{\left(gm\right)}\times 1000}{V_{\left(mL\right)}\times m_{\left(gm\right)}}$

whereas,

$W=$ wt. of solute $=1.25g$

$V=$ Volume of solvent $=25mL$

$M=$ Molarity of solvent $=0.25M$

$m=$ mol. wt. of solute $=?$

$\therefore 0.25=\frac{1.25\times 1000}{25\times m}$

$\Rightarrow m=200gm$

Hence the molecular mass of acid is 200 gm.