Question

the molarity of 2% Nacl solution is​

Answer 1

Solution: Formula of Molarity = No. of Moles of Solute/Volume of soultion (in mL) × 1000

Let mass of total solution be 100 gram, then

→ Number of moles of NaCl = Given Mass/Molecular Mass

• Given Mass = 2/100 × 100 = 2 gram
• Molecular Mass = 23 + 35.5 = 58.5 g/mol

→ No. of moles of NaCl = 2 g/58.5 g/mol

→ No. of moles of NaCl = 0.0342

→ Volume of Solution = 100 gram

→ Volume = Mass/Density

• Density of water = 1 g/cm³

→ Volume = 100 g/1 g/cm³ = 100 cm³ or 100 mL

→ Molarity = 0.0342/100 × 1000

→ Molarity = 0.342 M