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

The uncertainty principle and the concept of wave nature of matter were proposed by ______ and ______ respectively. (Heisenberg Schrodinger, Maxwell, de Broglie)

The wavelength of a spectral line for an electronic transition is inversely related to :

The outermost electronic configuration of the most electronegative element is