Question

Aqueous hydrochloric acid HCl will react with solid sodium hydroxide NaOH

 to produce aqueous sodium chloride NaCl and liquid water H2O. Suppose 8.0 g of hydrochloric acid is mixed with 17.1 g of sodium hydroxide. Calculate the minimum mass of hydrochloric acid that could be left over by the chemical reaction. Round your answer to 2 significant digits. 

Answer 1

NaOH (aq) + HCl (aq) → NaCl (aq) + H₂O (l)

Moles of HCl $= \frac{8}{36}=0.22moles$

Moles of NaOH$=\frac{17.1}{40}=0.43moles$

$0.43-0.22= 0.21moles$

$0.21× 36=7.7grams$