Question

The number of moles of chloride ions in 250 mL of 4.00 M MgCl2is:

(a) 5.00 (b) 2.00 (c) 10.0 (d) 4.00

Answer 1

Moles of MgCl₂ = concentration x volume of solution in litres

= 4 x (250/1000) L

= 1 mol

MgCl₂ ——> Mg⁺² + 2Cl^-

One mole of MgCl₂ give 2 moles of Cl^-

Moles of chloride ion = 2 mol

Option B is correct