.15g of sodium chloride was dissolved in 120cm3 of distilled water. Calculate the

concentration of chloride ions in moles per litre. (Na = 23, Cl = 35.5)

1 answer

First, we need to find the moles of sodium chloride present in the solution.

To do this, we use the formula:
moles = mass / molar mass

Molar mass of NaCl = 23 + 35.5 = 58.5 g/mol

moles of NaCl = 0.15g / 58.5 g/mol = 0.00256 mol

Next, since each molecule of NaCl contains 1 chloride ion, the concentration of chloride ions in moles per liter is the same as the concentration of NaCl.

Concentration of chloride ions = 0.00256 mol / 0.12 L = 0.0213 mol/L

Therefore, the concentration of chloride ions in the solution is 0.0213 mol/L.