AS level Chemistry 6 mark help

Watch this thread
Den322221
Badges: 5
Rep:
? You'll earn badges for being active around the site. Rep gems come when your posts are rated by other community members.
#1
Report Thread starter 3 months ago
#1
Two white solids are known to be the compounds magnesium nitrate and barium nitrate. Both solids are soluble in water.
Tests were carried out on the two compounds and the following results were obtained.
Dilute sulfuric acid was added to an aqueous solution of each compound. One showed no change; the other reacted to form a white precipitate.
Dilute sodium hydroxide was added to an aqueous solution of each compound. One showed no change; the other reacted to form a white precipitate.
The solids were heated separately. Both decomposed to form a white residue, a brown gas and a gas which relit a glowing splint. However, one solid decomposed faster than the other.
Discuss how observations from all three tests can be used to identify the two solids.
You should include equations for any reactions that take place (state symbols are not required).
Last edited by Den322221; 3 months ago
0
reply
Den322221
Badges: 5
Rep:
? You'll earn badges for being active around the site. Rep gems come when your posts are rated by other community members.
#2
Report Thread starter 3 months ago
#2
Anyone know?
0
reply
BlueChicken
Badges: 14
Rep:
? You'll earn badges for being active around the site. Rep gems come when your posts are rated by other community members.
#3
Report 3 months ago
#3
(Original post by Den322221)
Two white solids are known to be the compounds magnesium nitrate and barium nitrate. Both solids are soluble in water.
Tests were carried out on the two compounds and the following results were obtained.
Dilute sulfuric acid was added to an aqueous solution of each compound. One showed no change; the other reacted to form a white precipitate.
Dilute sodium hydroxide was added to an aqueous solution of each compound. One showed no change; the other reacted to form a white precipitate.
The solids were heated separately. Both decomposed to form a white residue, a brown gas and a gas which relit a glowing splint. However, one solid decomposed faster than the other.
Discuss how observations from all three tests can be used to identify the two solids.
You should include equations for any reactions that take place (state symbols are not required).
Three tests are used here. Describe the test and the known outcomes for common metal ions. Then use the observed results here, to deduce what the solids are and the reactions that have taken place.

You should have examples of these tests in your notes, especially if you need them for exam questions.
0
reply
Den322221
Badges: 5
Rep:
? You'll earn badges for being active around the site. Rep gems come when your posts are rated by other community members.
#4
Report Thread starter 3 months ago
#4
(Original post by BlueChicken)
Three tests are used here. Describe the test and the known outcomes for common metal ions. Then use the observed results here, to deduce what the solids are and the reactions that have taken place.

You should have examples of these tests in your notes, especially if you need them for exam questions.
It says what the known compounds are, do I need to find out which compound is formed with each test?
And could you also please state the tests which are used because I cannot find any notes that I’ve taken on testing metal ions
Thanks anyways
0
reply
BlueChicken
Badges: 14
Rep:
? You'll earn badges for being active around the site. Rep gems come when your posts are rated by other community members.
#5
Report 3 months ago
#5
Yes, I would say you need to say which is formed in each test and therefore what was the starting compound - although you know you have two compounds, it doesn't say that you know which is which (you have two white solids that are soluble in water).

You need to look at tests for cations (and anions) and trends in group 2 elements. If yo don't have notes for this, maybe it is not in your current spec? I'd check that or ask your teacher/tutor.

These should help for the first two:
https://www.savemyexams.co.uk/a-leve...ions--cations/
https://pmt.physicsandmathstutor.com...%20A-level.pdf
https://pmt.physicsandmathstutor.com...d%20anions.pdf
https://www.chemguide.co.uk/inorgani...acids.html#top
https://www.chemguide.co.uk/inorgani...olubility.html

For the last one:
https://books.google.co.uk/books?id=...page&q&f=false

Hope that helps. Good luck!
0
reply
X

Quick Reply

Attached files
Write a reply...
Reply
new posts
Back
to top
Latest

Does school Maths prepare people well enough for the future?

Yes, it gives everyone a good foundation for any future path (49)
30.25%
Somewhat, if your future involves maths/STEM (71)
43.83%
No, it doesn't teach enough practical life skills (40)
24.69%
Something else (tell us in the thread) (2)
1.23%

Watched Threads

View All