A solid mixture (5.0 g) consisting of lead nitrate and sodium nitrate was headed below 600^oC until the weight of the residue was constant. If the loss in weight 28.0 percent, find the amount of lead nitrate and sodium nitrate in the mixture.

Calculate the molality of 1 litre solution of 93% H₂SO₄ (weight/volume). The density of the solution is 1.84 g/ml

An equal volume of a reducing agent is titrated separately with 1M KMnO₄ in acid neutral and alkaline media. The volumes of KMnO₄ required are 20 ml. in acid 33.4 ml. neutral and 100 ml in alkaline media. Find out the oxidation state of manganese in each reduction product. Give the balanced equations for all three half reactions. Find out the volume of 1M K₂Cr₂O₇ consumed; if the same volume of the reducing agent is titrated in acid medium.

A sample of hydrazine sulphate (N₂H₆SO₄) was dissolved in 100 ml. of water, 10 ml of this solution was reacted with excess of ferric chloride solution and warmed to complete the reaction. Ferrous ion formed was estimated and it required 20 ml of M/50 potassium permanganate solution. Estimate the amount of hydrazine sulphate in one litre of the solution.

Reaction:

4Fe³⁺ + N₂H₄ $$\to$$ N₂ + 4Fe²⁺ + 4H⁺

$$MnO_4^-$$ + 4Fe²⁺ + 8H⁺ $$\to$$ Mn²⁺ + 5Fe³⁺ + 4H₂O