100 mL of Na₃PO₄ solution contains 3.45 g of sodium. The molarity of the solution is _____________ $$\times$$ 10^$$-$$2 mol L^$$-$$1. (Nearest integer)

[Atomic Masses - Na : 23.0 u, O : 16.0 u, P : 31.0 u]

The overall stability constant of the complex ion [Cu(NH₃)₄]²⁺ is 2.1 $$\times$$ 10¹³. The overall dissociations constant is y $$\times$$ 10^$$-$$14. Then y is __________. (Nearest integer)

83 g of ethylene glycol dissolved in 625 g of water. The freezing point of the solution is ____________ K. (Nearest integer)

[Use : Molal Freezing point depression constant of water = 1.86 K kg mol^$$-$$1]

Freezing Point of water = 273 K

Atomic masses : C : 12.0 u, O : 16.0 u, H : 1.0 u]

The reaction rate for the reaction

[PtCl₄]^2$$-$$ + H₂O $$\rightleftharpoons$$ [Pt(H₂O)Cl₃]^$$-$$ + Cl^$$-$$

was measured as a function of concentrations of different species. It was observed that $${{ - d\left[ {{{\left[ {PtC{l_4}} \right]}^{2 - }}} \right]} \over {dt}} = 4.8 \times {10^{ - 5}}\left[ {{{\left[ {PtC{l_4}} \right]}^{2 - }}} \right] - 2.4 \times {10^{ - 3}}\left[ {{{\left[ {Pt({H_2}O)C{l_3}} \right]}^ - }} \right]\left[ {C{l^ - }} \right]$$.

where square brackets are used to denote molar concentrations. The equilibrium constant K_c = ____________ . (Nearest integer)