Question

A 20g mixture of CaCO3 and NaCl reacted with 1/20M 50ml of HCl then find the % composition of mixture?

Answer 1

Hi there,

Given

HCl volume = 50ml = 0.05 L

HCl molarity = 0.05 M

Mixture of CaCO3 and NaCl

So,

Number of HCl mols = 2.5×10^-3

Reaction between CaCO3 and HCl

CaCO3 + 2HCl = CaCl2 + H2O + CO2

According to the equation

1mol CaCO3 react with 2mol HCl

So,

number of CaCO3 mols react with 2.5×10^-3 of HCl is

2.5×10^-3 ×1 mol ÷ 2mol = 1.25 ×10^-3

Molar mass of CaCO3 is 100g

So,

Mass of CaCO3 in mixture is

0.125 g

Mass of NaCl = 20-0.125= 19.875 g

% = 0.125 ÷ 20 ×100 = 0.06% caco3

%= 19.875 ÷20 × 100 = 99.3 % NaCl

♡ Hope the answer is helpful

♡Plz mark it as brainliest