In Carius method of estimation of halogens, 250 mg of an organic compound gave 141 mg of AgBr. The percentage of bromine in the compound is: (at. Mass Ag = 108; Br = 80)

The molecular formula of a commercial resin used for exchanging ions in water softening is C₈H₇SO₃Na (Mol. Wt. 206). What would be the maximum uptake of Ca²⁺ ions by the resin when expressed in mole per gram resin?

The following reaction is performed at 298 K
2NO(g) + O₂ (g) $$\leftrightharpoons$$ 2NO₂ (g)
The standard free energy of formation of NO(g) is 86.6 kJ/mol at 298 K. What is the standard free energy of formation of NO₂(g) at 298 K? (KP = 1.6 × 10¹²)

The standard Gibbs energy change at 300 K for the reaction 2A $$\leftrightharpoons$$ B + C is 2494.2 J. At a given time, the composition of the reaction mixture is [A] = 1/2, [B] = 2 and [C] = 1/2. The reaction proceeds in the: [R = 8.314 J/K/mol, e = 2.718]