Question

How many grams of concentrated nitric acid solution should be used to prepare 250 mL of 2.0 M $HN{O}_3$? The concentrated acid is 70% $HN{O}_3$.

• A. 70.0 g conc. $HN{O}_3$
• B. 54.0 g conc. $HN{O}_3$
• C. 45.0 g con. $HN{O}_3$
• D. 90.0 G con. $HN{O}_3$

Answer 1

The correct option is C 45.0 g con. $HN{O}_3$

$Molarity=\frac{W\times 1000}{M_W\times So{l}_{\left(ml\right)}}\Rightarrow 2=\frac{W}{63}\times \frac{1000}{250}$
$W=\frac{63}{2}g;Massofacid\times \frac{70}{100}\frac{63}{2}$
Mass of acid = 45 g