Answer:
47.2 g
Explanation:
Data given:
mass of Sodium oxide (Na₂O) = 25 grams
mass of potassium chloride (KCl) = excess
amount of sodium chloride (NaCl) = ?
Solution:
First we look for reaction of sodium oxide with potassium chloride.
Na₂O + 2 KCl -----------> 2 NaCl + K₂O
As we know that potassium chloride is in excess amount and sodium oxide is 25 g so it means sodium oxide is a limiting reactant and amount of sodium chloride depends on the amount of sodium oxide.
So, now we will look for mole mole ration of Na₂O to NaCl.
Na₂O + 2 KCl -----------> 2 NaCl + K₂O
1 mol 2 mol
from above equation we come to know that 1 mole of Na₂O gives 2 moles of NaCl.
Now convert moles to mass
As we Know
Molar mass of Na₂O = 2(23) + 16 = 62 g/mol
Molar mass of NaCl = 23 + 35.5 = 58.5 g/mol
So
Na₂O + 2 KCl -----------> 2 NaCl + K₂O
1 mol (62 g/mol) 2 mol (58.5 g/mol)
62 g 117 g
So, it means that 62 g of Na₂O produce 117 g of NaCl then how many grams of NaCl will be produce by 25 g of Na₂O
Apply unity formula
62 g of Na₂O ≅ 117 g of NaCl
25 g of Na₂O ≅ X g of NaCl
Do cross multiplication
X g of NaCl = 117 g x 25 g / 62 g
X g of NaCl = 47.2 g
So,
25 g of Na₂O gives 47.2 grams of NaCl.
