Testing Cations Flashcards
1
Q
How do you set up a clean wire loop?
A
Dip it into hydrochloric acid before each test.
2
Q
What materials can you use for the loop?
A
Very unreactive materials like
- nichrome
- platinum
3
Q
Li+ solid
In Flame
A
Red
4
Q
Na+ solid
In Flame
A
Yellow
5
Q
K+ solid
In Flame
A
Lilac/Purple
6
Q
Ca2+ solid
In Flame
A
Orange - Red
7
Q
Cu2+ solid
In Flame
A
Blue - Green
8
Q
When are Sodium hydroxides used to identify ions?
A
When metals are in solutions
9
Q
How does Sodium hydroxide identify an ion?
A
Will displace with metal and form an insoluble precipitate of a colour that correlates with the ion
10
Q
Al3+
Precipitate
A
White
11
Q
Cu2+
Precipitate
A
Blue
12
Q
Fe2+
Precipitate
A
Green
13
Q
Fe3+
Precipitate
A
Brown
14
Q
Ca2+
Precipitate
A
White
15
Q
What is the check for Ammonium ions?
A
- Add Sodium Hydroxide to solution and gently heat
- If gas given off turns damp red litmus, blue then ammonia is present.
- Also a strong smell indicates that ammonia is present.
