In the analysis of 0.5 g sample feldspar, a mixture of chlorides of sodium and potassium is obtained which weighs 0.1180g. Subsequent treatment of mixed chlorides with silver nitrate gives 0.2451 g of silver chloride. What is the percentage of sodium oxide and potassium oxide in feldspar.

The number of neutrons in dipositive zinc ion with mass number 70 is

The compound which contains both ionic and covalent bonds is

The octet rule is not valid for the molecule