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Question
Define ‘formula mass’ of a compound.
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Solution
Formula mass of a compound is the relative mass of its 'formula unit' compared to the mass of a carbon-12 atom (which has a mass of exactly 12 units).
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Match the names of ions and radicals from 1 to 10 with their correct answer from A to Q.
| Column A | Column B |
| 1. Hypochlorite | A: Hg2+ |
| 2. Permanganate | B: \[\ce{MnO_4^1-}\] |
| 3. Plumbous | C: Sn4+ |
| 4. Zincate | D: Pb2+ |
| 5. Nitride | E: Sn2+ |
| 6. Mercuric | F: Pb4+ |
| 7. Stannic | G: \[\ce{SO_3^2-}\] |
| 8. Nitrite | H: N3- |
| 9. Sulphite | I: \[\ce{NO_2^1-}\] |
| 10. Dichromate | J: \[\ce{MnO_4^2-}\] |
| K: Hg1+ | |
| L: \[\ce{SO_4^2-}\] | |
| M: CIO1- | |
| N: \[\ce{ZnO_2^2-}\] | |
| O: \[\ce{Cr_2O_7^2-}\] | |
| P: \[\ce{CrO_4^2-}\] | |
| Q: \[\ce{ClO_3^1-}\] |
