smc-4258-35-Valency

CHEMISTRY, M1 EQ-Bank 21

Explain, with the use of a diagram or otherwise, why the oxide ion has a valency of minus 2. (2 marks)

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→ An oxide ion is the ion of the element oxygen \(\ce{(O)}\), atomic weight 16.

→ An oxygen atom has 8 electrons and 8 protons. It has 2 electrons in its inner shell and 6 electrons in its valence (outer) shell.

→ An oxygen atom can gain 2 electrons to form a stable octet in its valence shell and therefore has a valency of minus 2.

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→ An oxide ion is the ion of the element oxygen \(\ce{(O)}\), atomic weight 16.

→ An oxygen atom has 8 electrons and 8 protons. It has 2 electrons in its inner shell and 6 electrons in its valence (outer) shell.

→ An oxygen atom can gain 2 electrons to form a stable octet in its valence shell and therefore has a valency of minus 2.

What are the valencies of the following simple and polyatomic ions

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i. Valency: Phosphate \((\ce{PO4}) = 3^{-}\)

ii. Valency: Zinc \((\ce{Zn}) = 2^{+}\)

iii. Valency: Carbonate \((\ce{CO3}) = 2^{-}\)

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i. Valency: Phosphate \((\ce{PO4}) = 3^{-}\)

ii. Valency: Zinc \((\ce{Zn}) = 2^{+}\)

iii. Valency: Carbonate \((\ce{CO3}) = 2^{-}\)

What are the valencies of the following simple ions

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i. Valency: Barium \((\ce{Ba}) = 2^{+}\)

ii. Valency: Phosphide \((\ce{P}) = 3^{-}\)

iii. Valency: Silver \((\ce{Ag}) = 1^{+}\)

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i. Valency: Barium \((\ce{Ba}) = 2^{+}\)

ii. Valency: Phosphide \((\ce{P}) = 3^{-}\)

iii. Valency: Silver \((\ce{Ag}) = 1^{+}\)