A sample of an alloy weighing `0.50 g` and containing 90% `Ag` was dissolved in concentrated `HNO_(3)`. `Ag` was analysed by volhard method in which `25 mL` of `KCNS` was required for complete neutralisation. Determine the normality of `KCNS`.

4.0 g of a mixture of Nacl and Na_(2) CO_(3) was dissolved in water and volume made up to 250 mL . 25 mL of this solution required 50 mL of N//10 HCl for complete neutralisation. Calculate the percentage composition of the original mixture.

4.0 g of a mixture of Nacl and Na_(2) CO_(3) was dissolved in water and volume made up to 250 mL . 25 mL of this solution required 50 mL of N//10 HCl for complete neutralisation. Calculate the percentage composition of the original mixture.

A sample of sodium carbonate contains sodium also. 1.5 g of the sample is dissolved in water and volume raised to 250 mL. 25 mL of this solution requires 20 mL of (N)/(10)H_(2)SO_(4) solution for neutralisation. Calculate the percentage of sodium carbonate in the sample.

An organic compound contains 69.4% carbon and 5.8% hydrogen. A sample of 0.303 g of this compound was analysed for nitrogen by Kjeldahl's method. The ammonia evolved was absorbed in 50 mL of 0.05 M H_2 SO_4 . The excess acid required 25 mL of 0.1 M NaOH for neutralisation. Determine the molecular formula of the compound, if its molecular mass is 121.

4.08 g of a mixture of BaO and an unknown carbonate MCO_(3) was heated strongly. The residue weighed 3.64 g . This was dissolved in 100 mL of 1 N HCl . The excess of acid required of 16 mL of 2.5 N NaOH for complete neutralisation. Identify the matal M .