Question

A. Choose from the following list, as what matches the descriptions given below.
[0^2-, 0xygen, NH4+, OH-, H2O, NH4CI, HCI, Ca2+, magnesium oxide, helium]

1. A noble gas having only two electrons in its valence shell.
2. A cation whose electron configuration resembles argon.
3. An anion whose electron configuration resembles neon.
4. A metallic oxide formed by the actual transfer of two electrons from the metallic atom.
5. A molecule of a non-metal formed by sharing two pairs of electrons.
6. A molecule of polar covalent compound.
7. A radical having a covalent and coodinate valent bond.
8. A salt having an ionic, a covalent and not a coordinate valent bond.
9. A molecule of two non-metals having two lone electron pairs.
10. An anion formed by the loss of one hydrogen atom from the molecule of water.

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Answer 1

Answer:

1. Helium
2. Ca2+
3. OH-

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