What is the percent yield for Na plus Cl2 -- 2NaCl?

Answer 1

Percentage yield is given as:-

%yield = (mass of product obtained experimentally/theoretical yield)x100

where the theoretical yield is the maximum mass which could possibly be obtained assuming 100% stoichiometry.

So, say as an example if you start with 71g of Cl2 then:-

mol = mass/Mr Mr of Cl2 = 71

mol = 71/71

mol = 1 of Cl2

This is the limiting reagent, assuming we have at least 46g of sodium, thus we double this number as the reaction is 1:2

1 mole Cl2---->2moles NaCl

again we use:-

mole = mass/Mr Mr of NaCl = 58.5

2 x Mr = mass

2 x 58.5 = mass

maximum mass of NaCl possible = 117g

If the reaction is carried out and we achieve 100g of NaCl then:-

%yield = (100/117) x 100

= 85.5%

Answer 2

The theoretical yield of 2NaCl is based on stoichiometry, while the actual yield is based on the amount of product obtained in the reaction. The percent yield can be calculated by dividing the actual yield by the theoretical yield and multiplying by 100%. It gives an indication of how efficient the reaction was in producing the desired product.