Calculate the mass of sodium required to obtain 10.7 g of sodium chloride in an excess of chlorine

Calculate the mass of sodium required to obtain 10.7 g of sodium chloride in an excess of chlorine, the reaction scheme: 2Na + Cl2 = 2NaCl

Given:

m (NaCl) = 10.7 g

Find:

m (Na) -?

Solution:

2Na + Cl2 = 2NaCl, – we solve the problem, relying on the composed reaction equation:

1) Find the amount of sodium chloride obtained:

n (NaCl) = m: M = 10.7 g: 58.5 g / mol = 0.18 mol

2) We compose a logical expression:

If 2 mol Na gives 2 mol NaCl,

then x mol Na will give 0.18 mol NaCl,

then x = 0.18 mol.

3) Find the mass of sodium required for the full course of the reaction:

m (Na) = n * M = 0.18 mol * 23 g / mol = 4.14 g.

Answer: m (Na) = 4.14 g.