When 35 mL of 0.15 M lead nitrate solution is mixed with 20 mL of 0.12 M chromic sulphate solution, _________ $$\times$$ 10^$$-$$5 moles of lead sulphate precipitate out. (Round off to the Nearest Integer).

Complete combustion of 750 g of an organic compound provides 420 g of CO₂ and 210 g of H₂O. The percentage composition of carbon and hydrogen in organic compound is 15.3 and ___________ respectively. (Round off to the Nearest Integer).

$$2MnO_4^ - + b{C_2}O_4^{2 - } + c{H^ + } \to xM{n^{2 + }} + yC{O_2} + z{H_2}O$$

If the above equation is balanced with integer coefficients, the value of c is ___________. (Round off to the Nearest Integer).

A 6.50 molal solution of KOH (aq.) has a density of 1.89 g cm^$$-$$3. The molarity of the solution is ____________ mol dm^$$-$$3. (Round off to the Nearest Integer).

[Atomic masses : K : 39.0 u; O : 16.0 u; H : 1.0 u]