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# Chemistry calculating gas question

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1. Can anyone explain how to work out c? I've done the empirical formula, ions and I've worked out what B is.0, it's what gas C is that is the problem
2. (Original post by AqsaMx)
Can anyone explain how to work out c? I've done the empirical formula, ions and I've worked out what B is.0, it's what gas C is that is the problem
You've worked out the formula of A and B; you know that A -> B + C + n H2O. So, take the elements in B away from the formula of A to get what will be in the gas and water; then take away hydrogen and oxygen at a 2:1 ratio to account for the water; what's left will be your gas.
3. (Original post by Stiff Little Fingers)
You've worked out the formula of A and B; you know that A -> B + C + n H2O. So, take the elements in B away from the formula of A to get what will be in the gas and water; then take away hydrogen and oxygen at a 2:1 ratio to account for the water; what's left will be your gas.
Isn't it a calculation as it mentions RTP?
4. (Original post by AqsaMx)
Isn't it a calculation as it mentions RTP?
You can't calculate the gas from the density. You're working out what the products of the degradation reaction are; the density is just possibly useful info about the gas if you have a couple of possibilities.

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5. (Original post by Stiff Little Fingers)
You can't calculate the gas from the density. You're working out what the products of the degradation reaction are; the density is just possibly useful info about the gas if you have a couple of possibilities.

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I see what you mean but the MS gives a mark for correctly calculating the mass :
1.17 x 24 = 28 I don't get this calculation though

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