Feynboy
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I thought the answer was B, lilac means it is potassium. And the metal oxide is basic?
The mark scheme says it's D.
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Plantagenet Crown
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(Original post by Feynboy)
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I thought the answer was B, lilac means it is potassium. And the metal oxide is basic?
The mark scheme says it's D.
How could potassium oxide react with water to give off hydrogen gas?
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Feynboy
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(Original post by Plantagenet Crown)
How could potassium oxide react with water to give off hydrogen gas?
oh yeah. Ok then
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charco
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(Original post by Feynboy)
oh yeah. Ok then
Hydrides of group 1, such as KH, contain the H- ion.

They react with water to form:

H- + H2O --> H2 + OH-

hydrogen and hydroxide ions ...

Interestingly, this is an example of a synproportionation (comproportionation) reaction where one element in two different oxidation states becomes the same oxidation state. It is the chemical opposite of disproportionation.
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Feynboy
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(Original post by charco)
Hydrides of group 1, such as KH, contain the H- ion.

They react with water to form:

H- + H2O --> H2 + OH-

hydrogen and hydroxide ions ...

Interestingly, this is an example of a synproportionation (comproportionation) reaction where one element in two different oxidation states becomes the same oxidation state. It is the chemical opposite of disproportionation.
Thank you
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