Single Unknown (3688)
The observed flame colour, line position, wavelengths and intensity of the unknown salt is the
same as lithium chloride therefore the unknown solution must be lithium chloride
Mixed Unknown (9121)
The mixed solution is a combination of lithium chloride and calcium chloride. The unknown
solution showed intense red lines like lithium chloride but also shows an intense orange like
calcium chloride. All the other salts show an intense blue line which this unknown solution does
not show therefore I could eliminate them.
Part 2
1. Differences between 0.005M and 0.025M of KMnO4
- 0.005M had 6 visible lines
- 0.025M only had 4 barely visible lines
- The bottle appeared light purple when held up to the light in 0.005M
- The bottle appeared a slightly darker purple bottle for 0.025M
- Blue was the most intense for both however it was still really faint on 0.025M
2. Does the spectrum agree with the KMnO4 solutions colour?
- The colour of the solution was purple and the lines on the spectrum were blue,
purple, and yellow
- The spectrum did not agree with the colour we saw, the solution had a colour
because it absorbed specific wavelengths of visible light and the colour we see in the
solution is transmitted wavelengths that were not absorbed
- The human eye can only see one solid colour therefore the lines we see on the
spectrum are the components that make up the purple colour our eyes perceive
3. Difference between spectrum of lamp and the KMnO4 solution
- The spectrum of lamp shown more lines with more of an intense colour than the
KMnO4 spectrum
- This is because when light is passed from the lamp through the solution the
molecules in the solution absorb the energy from the lamp causing the KMnO4
spectrum when placed in front of the light to have fainter lines and even some that
aren’t there at all
4. Does your observations support the Beer Lambert Law?
- This law looks at the light to the properties of the solution in which the light is
passing such as concentration and absorbance
- It does support the law because in the experiment the more concentrated solution
(0.025M) absorbed more light as you can tell by the faint lines of the spectrum
- This proves the more concentrated a solution relates to how absorbent to light it is
The observed flame colour, line position, wavelengths and intensity of the unknown salt is the
same as lithium chloride therefore the unknown solution must be lithium chloride
Mixed Unknown (9121)
The mixed solution is a combination of lithium chloride and calcium chloride. The unknown
solution showed intense red lines like lithium chloride but also shows an intense orange like
calcium chloride. All the other salts show an intense blue line which this unknown solution does
not show therefore I could eliminate them.
Part 2
1. Differences between 0.005M and 0.025M of KMnO4
- 0.005M had 6 visible lines
- 0.025M only had 4 barely visible lines
- The bottle appeared light purple when held up to the light in 0.005M
- The bottle appeared a slightly darker purple bottle for 0.025M
- Blue was the most intense for both however it was still really faint on 0.025M
2. Does the spectrum agree with the KMnO4 solutions colour?
- The colour of the solution was purple and the lines on the spectrum were blue,
purple, and yellow
- The spectrum did not agree with the colour we saw, the solution had a colour
because it absorbed specific wavelengths of visible light and the colour we see in the
solution is transmitted wavelengths that were not absorbed
- The human eye can only see one solid colour therefore the lines we see on the
spectrum are the components that make up the purple colour our eyes perceive
3. Difference between spectrum of lamp and the KMnO4 solution
- The spectrum of lamp shown more lines with more of an intense colour than the
KMnO4 spectrum
- This is because when light is passed from the lamp through the solution the
molecules in the solution absorb the energy from the lamp causing the KMnO4
spectrum when placed in front of the light to have fainter lines and even some that
aren’t there at all
4. Does your observations support the Beer Lambert Law?
- This law looks at the light to the properties of the solution in which the light is
passing such as concentration and absorbance
- It does support the law because in the experiment the more concentrated solution
(0.025M) absorbed more light as you can tell by the faint lines of the spectrum
- This proves the more concentrated a solution relates to how absorbent to light it is
