| 1. | The oxidation state and coordination number (or covalency) of \(\mathrm{Al}\) in\( \left[\mathrm{AlCl}\left(\mathrm{{H}_2 {O}}\right)_5\right]^{2+} \) are +3 and 6, respectively. |
| 2. | \(\mathrm{Na}_2 \mathrm{O}\) is a basic oxide and \(\mathrm{Cl}_2 \mathrm{O}_7\) is an acidic oxide |
| 3. | The following four species are called isoelectronic species: \( \mathrm{O}^{2-}, \mathrm{F}^{-}, \mathrm{Na}^{+} \mathrm{and}~ \mathrm{Mg}^{2+}\) |
| 4. | Among the four species \(\mathrm{Mg}, \mathrm{Al}, \mathrm{Mg}^{2+}\) and \(\mathrm{A l^{3+},}\) the smallest one is \(\mathrm{Al}.\) |
| 1. | NO, ZnO, CO2, CaO | 2. | ZnO, NO, CaO, CO2 |
| 3. | NO, CO2, ZnO, CaO | 4. | NO, CO2, CaO, ZnO |
| 1. | Mg2X3 | 2. | MgX2 |
| 3. | Mg2X | 4. | Mg3X2 |