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Chemistry transition work help

Hi, so i need someones help to explain how to do a question set as transition work for a level chemistry. In GCSE i was never taught this so i am a bit confused on how to do it. All help appreciated!

2. When an acid is added to water it dissociates to form H+ ions (which make it acidic) and an
anion. These acidic hydrogen atoms can be used to determine the charge on the anion.
Deduce the charge on the anions in the following acids. The acidic H atoms, H+

, have been
underlined for you. (5 marks)
a. H2SO3
b. HNO3
c. H3PO4
d. HCOOH
e. H2CO3
Reply 1
Original post by LokiSonOfOdin
Hi, so i need someones help to explain how to do a question set as transition work for a level chemistry. In GCSE i was never taught this so i am a bit confused on how to do it. All help appreciated!

2. When an acid is added to water it dissociates to form H+ ions (which make it acidic) and an
anion. These acidic hydrogen atoms can be used to determine the charge on the anion.
Deduce the charge on the anions in the following acids. The acidic H atoms, H+

, have been
underlined for you. (5 marks)
a. H2SO3
b. HNO3
c. H3PO4
d. HCOOH
e. H2CO3


If you remove 1x H+ from H2SO3, what will be left behind?
Original post by Pigster
If you remove 1x H+ from H2SO3, what will be left behind?

erm HSO3 ?
Reply 3
Original post by LokiSonOfOdin
erm HSO3 ?

But... you started with a compound (H2SO3) which didn't have a charge, and you pulled off an H+ which has a charge... you can't magic charge out of thin air. How do you square that circle?
Original post by Pigster
But... you started with a compound (H2SO3) which didn't have a charge, and you pulled off an H+ which has a charge... you can't magic charge out of thin air. How do you square that circle?

Ohh.. so would it be HSO3- ? To even out the charges?
Reply 5
Original post by rachaelv
Ohh.. so would it be HSO3- ? To even out the charges?

Bingo.

Now, do the rest.

Be careful with d. as you have a choice. You may need to do a little research.
Original post by Pigster
Bingo.

Now, do the rest.

Be careful with d. as you have a choice. You may need to do a little research.

thank you, this was extremely helpful and I got full marks from it :smile:

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