A 10 mg effervescent tablet containing sodium bicarbonate and oxalic acid releases 0.25 ml of CO₂ at T = 298.15 K and p = 1 bar. If molar volume of CO₂ is 25.0 L under such condition, what is the percentage of sodium bicarbonate in each tablet ?
[Molar mass of NaHCO₃ = 84 g mol^–1]

The amount of sugar (C₁₂H₂₂O₁₁) required to prepare 2L of its 0.1 M aqueous solution is :

For the following reaction, in the mass of water produced from 445 g of C₅₇H₁₁₀O₆ is :

2C₅₇H₁₁₀O₆(s) + 163 O₂(g) $$ \to $$ 114 CO₂(g) + 110 H₂O(l)

A solution of sodium sulphate contains 92 g of Na⁺ ions per kilogram of water. The molality of Na⁺ ions in that solution in mol kg^$$-$$1 is :