Flame Emmission Spectroscopy

Question 1

What is the big idea with flame photometry/ flame emmission spectroscopy ?

Answer 1

When metal ions are heated they emit light and the wavelengths of the light (the colour you can see) are specific to that metal ion

Question 2

Why is this better than the standard flame test? Give two reasons

Answer 2

1. The standard flame test is limited because if metals produce similar colours then we cannot tell them apart
2. If the sample contains multiple metals the flames can become mixed

Question 3

How does flame spectroscopy over come the problems that can occur in the standard flame tests?

Answer 3

Uses a spectroscope- it detects the individual wavelengths of light that are emitted

Question 4

What are some benefits of spectroscopy ?

Answer 4

• Every different metal ion has a unique line spectrum meaning we can see exactly what ion it could be
• The intensity of the lines can tell us the concentration of the ion

Question 5

What is the main advantage of flame emission spectroscopy (the biggest one) ?

Answer 5

If a sample contains multiple different metal ions
The line spectrum will show the lines for all of them
So we can see what ions are in the solution

Question 6

How do we do this in exams ?

Answer 6

Just look at which lines share lines with the unknown sample but all of them have to share
Basically means those ions are present

Question 7

What are the pros and cons of instrumental methods ?

Answer 7

Uses expensive machines but give better results
- very accurate
-very sensitive
- very fast

Question 8

What are the pros and cons for manual test (flame test)

Answer 8

Cheap and basic but somewhat efficient