The correct option is (b) 7 g
16.9% solution of AgNO3, means 16.9 g of AgNO3 in 100 mL of solution.
16.9 g of AgNO3 in 100 mL solution = 8.45 g of AgNO3 in 50 mL solution.
Similarly. 5.8% of NaCl in 100 mL solution = 2.9 g of NaCl in 50 mL solution.
The reaction can be represented as :
AgNO3 + NaCl → AgCl + NaNO3