Na+CL2=2NACL is the balanced reaction for the formation of table salt. Given 20 grams of Na and 10 grams of Cl2, which reactant is in excess? How much NaCL should be produced from these amounts of the two reactants?

Excess reactant : Na

NaCl produced : = 16.497 g

Given

Reaction(balanced)

2Na + Cl₂⇒ 2NaCl

20 g Na

10 g Cl₂

Required

Excess reactant

NaCl produced

Solution

mol Na(Ar = 23 g/mol) :

= 20 : 23 = 0.87

mol Cl₂(MW=71 g/mol):

= 10 : 71 g/mol = 0.141

mol : coefficient :

Na = 0.87 : 2 = 0.435

Cl₂ = 0.141 : 1 = 0.141

Limiting reactant : Cl₂(smaller ratio)

Excess reactant : Na

Mol NaCl based on mol Cl₂, so mol NaCl :

= 2/1 x mol Cl₂

= 2/1 x 0.141

= 0.282

Mass NaCl :

= 0.282 x 58.5 g/mol

= 16.497 g