C4.2.2 - Detecting Cations Flashcards
What happens when energy is transferred into electrons?
They move into higher electron levels.
What occurs when electrons move back into their original electron levels after being heated?
The energy lost is transferred to the surrounding as light
Why do metals give off different colours in the flame test?
Ions emit different types of colour and radiation when moving back into their original energy levels
What colour does lithium emit when used in the flame test?
Red
What colour does sodium emit when used in the flame test?
Yellow
What colour does potassium emit when used in the flame test?
Lilac
What colour does calcium emit when used in the flame test?
Orange-red
What colour does copper emit when used in the flame test?
Green-blue
What so the wire used in the flame test made of?
Nichrome
Why is nichrome used for the flame test?
It does not emit any colours when heated so there is no contamination
Describe the flame test.
Dip the nichrome wire loop into the solution.
Use the handle to hold the nichrome into the flame.
Record the colour emitted.
Clean the nichrome wire loop by dipping it in hydrochloric acid and then rinsing it with distilled water
Why do you have to clean the nichrome wire loop after each flame test?
So there is no contamination from the previous test
Are most metal hydroxides soluble or insoluble?
Insoluble
Why is sodium hydroxide often used in experiments?
It is one of the only soluble hydroxides
Do different metals produce different coloured precipitates?
Yes
