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प्रश्न
Write the formula of the following compound:
Aluminium oxide
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उत्तर
Aluminium oxide - Al2O3 - `"Al"^(3+)["O"]^(2-)`
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संबंधित प्रश्न
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Complete the following crossword puzzle (Fig. 3.1) by using the name of the chemical elements. Use the data given in Table.
| Across | Down | ||
| 2 | The element used by Rutherford during his α–scattering experiment | 1 | A white lustrous metal used for making ornaments and which tends to get tarnished black in the presence of moist air |
| 3 | An element which forms rust on exposure to moist air | 4 | Both brass and bronze are alloys of the element |
| 5 | A very reactive non–metal stored under water | 6 | The metal which exists in the liquid state at room temperature |
| 6 | Zinc metal when treated with dilute hydrochloric acid produces a gas of this element which when tested with burning splinter produces a pop sound. | 8 | An element with symbol Pb |
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Play a game for writing formula.
Example 1: Make placards with symbols and valencies of the elements separately. Each student should hold two placards, one with the symbol in the right hand and the other with the valency in the left hand. Keeping the symbols in place, students should criss-cross their valencies to form the formula of a compound.
