explain the variation in melting point and electrical conductivity in terms of the structure and bonding of the elements

write formulas of ionic compounds from ionic charges and oxidation numbers (shown by a Roman numeral), including: (a) the prediction of ionic charge from the position of an element in the Periodic Table (b) recall of the names and formulas for the following ions: \(NO_3^-\), \(CO_3^{2-}\), \(SO_4^{2-}\), \(OH^-\), \(NH_4^+\), \(Zn^{2+}\), \(Ag^+\), \(HCO_3^-\), \(PO_4^{3-}\)

explain, including by use of an equation, the use of chlorine in water purification to include the production of the active species HOCI and CIO\(^-\) which kill bacteria