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Attachment 621764Can someone tell me how would you identify the following compounds. How would you test for the following compounds?
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(Original post by Reality Check)
and the compounds are...(drum roll)?
and the compounds are...(drum roll)?
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#4
Look at the powerpoint slide again, carefully. What do you notice in the blue bar?
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(Original post by Reality Check)
Look at the powerpoint slide again, carefully. What do you notice in the blue bar?
Look at the powerpoint slide again, carefully. What do you notice in the blue bar?
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#6
There are a series of characteristic tests for anions and cations that you need to know, like flame tests. Different exam boards require knowledge of different ones 
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#7
(Original post by Lucky10)
Thermal decomposition?
Thermal decomposition?
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(Original post by Reality Check)
Exactly. And one of the ways you can identify compounds using thermal composition is...?
Exactly. And one of the ways you can identify compounds using thermal composition is...?
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#9
(Original post by Lucky10)
Flame tests?
Flame tests?
- Exactly. And you got to the answer without having to be told.Have a look at flame colours, and see whether you can get anywhere with it. Post back if you need any more help, or check what you've got.
Well done.
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(Original post by Reality Check)
- Exactly. And you got to the answer without having to be told.
Have a look at flame colours, and see whether you can get anywhere with it. Post back if you need any more help, or check what you've got.
Well done.
- Exactly. And you got to the answer without having to be told.Have a look at flame colours, and see whether you can get anywhere with it. Post back if you need any more help, or check what you've got.
Well done.
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#11
Have a look through your notes to find the flame colours produced by different metal ions. If you really can't find them, then get back to me.
Some group 2 metals can be identified by flame tests in the same way as group 1. Have a look at the compounds you're needing to differentiate and see which are in group 1 and which are in group 2. Remember too that you might NOT be able to positively identify one of them, but if you've identified the others you can do it by a process of elimination.
You can't test group 7 elements using a flame test. Why?
Some group 2 metals can be identified by flame tests in the same way as group 1. Have a look at the compounds you're needing to differentiate and see which are in group 1 and which are in group 2. Remember too that you might NOT be able to positively identify one of them, but if you've identified the others you can do it by a process of elimination.
You can't test group 7 elements using a flame test. Why?
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(Original post by Reality Check)
Have a look through your notes to find the flame colours produced by different metal ions. If you really can't find them, then get back to me.
Some group 2 metals can be identified by flame tests in the same way as group 1. Have a look at the compounds you're needing to differentiate and see which are in group 1 and which are in group 2. Remember too that you might NOT be able to positively identify one of them, but if you've identified the others you can do it by a process of elimination.
You can't test group 7 elements using a flame test. Why?
Have a look through your notes to find the flame colours produced by different metal ions. If you really can't find them, then get back to me.
Some group 2 metals can be identified by flame tests in the same way as group 1. Have a look at the compounds you're needing to differentiate and see which are in group 1 and which are in group 2. Remember too that you might NOT be able to positively identify one of them, but if you've identified the others you can do it by a process of elimination.
You can't test group 7 elements using a flame test. Why?
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#13
(Original post by Lucky10)
As they are halogens, could you do the first one for me as an example. Thank you for this!!
As they are halogens, could you do the first one for me as an example. Thank you for this!!
Exactly! Flame tests can only test for metal ions (if you want to know the science behind it, when you heat different metals, their atoms (what they're made up of) absorb the heat as energy - they can then release this energy back, and it's released in the form of light, which is the colours that you see - different metals absorb different amounts of energy, and the colours they 'release' are consequently different too).
I don't understand what you mean about 'do the first one for you' - your list doesn't contain any halogens?! What are you referring to here?
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(Original post by Reality Check)
You're welcome.
Exactly! Flame tests can only test for metal ions (if you want to know the science behind it, when you heat different metals, their atoms (what they're made up of) absorb the heat as energy - they can then release this energy back, and it's released in the form of light, which is the colours that you see - different metals absorb different amounts of energy, and the colours they 'release' are consequently different too).
I don't understand what you mean about 'do the first one for you' - your list doesn't contain any halogens?! What are you referring to here?
You're welcome.
Exactly! Flame tests can only test for metal ions (if you want to know the science behind it, when you heat different metals, their atoms (what they're made up of) absorb the heat as energy - they can then release this energy back, and it's released in the form of light, which is the colours that you see - different metals absorb different amounts of energy, and the colours they 'release' are consequently different too).
I don't understand what you mean about 'do the first one for you' - your list doesn't contain any halogens?! What are you referring to here?
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#15
(Original post by Lucky10)
I'm referring to the attachment. And so how would you test for halogens?
I'm referring to the attachment. And so how would you test for halogens?
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#16
(Original post by benjamin_graham)
.
.
Thank you.
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#17
(Original post by Lucky10)
I'm referring to the attachment. And so how would you test for halogens?
I'm referring to the attachment. And so how would you test for halogens?
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(Original post by Reality Check)
Ok, I don't see anywhere on the powerpoint any halogens, or a mention of where you should be testing for them. Can you tell me where on this powerpoint this is mentioned?
Ok, I don't see anywhere on the powerpoint any halogens, or a mention of where you should be testing for them. Can you tell me where on this powerpoint this is mentioned?
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#19
(Original post by Lucky10)
It was just part of the task but instead I wrote it down which was how would you test for group 7 elements
It was just part of the task but instead I wrote it down which was how would you test for group 7 elements
Well, there's several tests for halogens and halogen ions (=halides). Some involve heating wire wool in the presence of them - the wire wool reacts differently. Others involve their ions. Fluorine is so reactive and dangerous that you wouldn't test for that directly - it will combust pretty much anything it comes into contact with, including paper.
Without knowing your exact learning schedule, I'm not sure how much detail to give you regarding the testing of the halogens - I don't want to give you a huge amount of information you don't need.
How are you getting on identifying these metal ions?
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(Original post by Reality Check)
Ah, I see
Well, there's several tests for halogens and halogen ions (=halides). Some involve heating wire wool in the presence of them - the wire wool reacts differently. Others involve their ions. Fluorine is so reactive and dangerous that you wouldn't test for that directly - it will combust pretty much anything it comes into contact with, including paper.
Without knowing your exact learning schedule, I'm not sure how much detail to give you regarding the testing of the halogens - I don't want to give you a huge amount of information you don't need.
How are you getting on identifying these metal ions?
Ah, I see
Well, there's several tests for halogens and halogen ions (=halides). Some involve heating wire wool in the presence of them - the wire wool reacts differently. Others involve their ions. Fluorine is so reactive and dangerous that you wouldn't test for that directly - it will combust pretty much anything it comes into contact with, including paper.
Without knowing your exact learning schedule, I'm not sure how much detail to give you regarding the testing of the halogens - I don't want to give you a huge amount of information you don't need.
How are you getting on identifying these metal ions?
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