Question

How many moles of salt are in 13.8 g of sodium chloride?

Answer 1

Answer: 0.236 mol ≈ 0.24mol

Explanation:

to find the amount of moles of salt in 13.8g of sodium chloride, NaCl, we need to find the mass of sodium in g/mol first.

To find the amount of sodium in g/mol, we sum up the individual masses of

sodium and chloride.

Mass of one mole of sodium = 23g

Mass of one mole of chlorine = 35.4g

Mass of sodium chloride = ( Mass of Na + Mass of Cl)

mass of NaCl = (23 + 35.4) = 58.4g/mol

∴ 1 mole of NaCl = 58.4g

   x moles of NaCl = 13.8g

By cross multiplication, we have

13.8g × 1 mol ÷ 58.4g

=0.236mol ≈ 0.24mol

Answer 2

Answer: 0.24 moles

Explanation:

Molecular Mass of NaCl (23 + 35.5) = 58.5g

58.5g of Sodium Chloride -------> 1 mole of NaCl

∴ 13.8g of Sodium Chloride  ------>  1 ÷58.5 x  13.8 = 0.2358974  ≈    0.24moles

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