The major product of the following reaction is :

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 :

In general, the properties that decrease and increase down a group in the periodic table, respectively, are :

The increasing order of pka of the following amino acids in aqueous solution is :

Gly, Asp, Lys, Arg