Saved Bookmarks
| 1. |
IlIBle of water molecules?10. Calculate the number of molecules of suiphur (S,) pres11. Calculate the number of aluminium ions present in 0.051 B16 g of solid sulphur.aluminium oxide. |
|
Answer» The molecules formula of sulphur is given to be S8 ( it Contains 8 atoms of sulphur ). So , the molecular mass of sulphur molecule is 32 × 8 = 256 u. This means that 1 mole of sulphur molecules is equal to 256 grams. Now, 256 g of sulphur = 1 mole of sulphur molecules So, 16 g of sulphur = 1/ 256 × 16 mole of sulphur molecules = 0.0625 mole of sulphur molecules Also, 1 mole of sulphur molecules = 6.023 × 10²³ molecules So, 0.0625 mole of sulphur molecules = 6.025 × 10²³ × 0.0625 molecules = 3.76 × 10²² molecules 1 mole of aluminium oxide (Al2O3) = 2*27 + 3 * 16 = 102 g i.e., 102 g of Al2O3 = 6.022 * 1023 molecules of Al2O3 Then, 0.051 g of Al2O3 contains = = 3.011 * 1020 molecules of Al2O3 The number of aluminium ions (Al3+) present in one molecule of aluminium oxide is 2. Therefore, the number of aluminium ions (Al3+) present in 3.011 * 1020 molecules (0.051 g ) of aluminium oxide (Al2O3) = 2 * 3.011 * 1020 = 6.022 * 1020=6142.44 |
|