4.6 - Chemical analysis Flashcards
1
Q
Test for hydrogen
A
- Collect sample of gas in test tube
- Ignite using lit splint
- Result = squeaky pop
2
Q
Test for oxygen
A
- Collect a sample of gas in test tube
- Place glowing splint in test tube
- Result = splint relights
3
Q
Chemical test for water
A
- Add anhydrous copper sulfate
- Result = Changes from white to blue
4
Q
Physical test for water
A
- Measure BP
- Result = BP is 100 degrees
5
Q
Test for carbon dioxide
A
- Bubble a sample of the gas through limewater.
- Result = solution turns cloudy
6
Q
Test for chlorine
A
- Place damp blue litmus paper in a sample of gas.
- Result = it turns white (bleaches).
7
Q
Test for ammonia
A
- Place damp red litmus paper in a sample of gas.
- Result = it turns blue
8
Q
How to conduct a flame test.
A
- Dip a piece of nichrome / platinum wire into hydrochloric acid. These wires don’t colour the flame, and the acid cleans the wire.
- Dip the wire into a sample of solid or solution. This causes some of the sample to stick onto the wire.
- Place the tip of the wire into a non-luminous Bunsen flame.
9
Q
What does a flame test test for?
A
What type of metal cation is in a substance
10
Q
Flame colour of lithium (Li) ?
A
Red
11
Q
Flame colour of sodium (Na) ?
A
Yellow
12
Q
Flame colour of potassium (K) ?
A
Lilac
13
Q
Flame colour of calcium (Ca) ?
A
Orange-red
14
Q
Flame colour of copper (Cu) ?
A
Blue-green
15
Q
How do you conduct a sodium hydroxide (NaOH) test?
A
- Dissolve the sample in water.
- Add a few drops of NaOH(aq).