Topic 9 - Seperate Chemistry Flashcards Preview

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Flashcards in Topic 9 - Seperate Chemistry Deck (36):
1

What colour flame would Li+ ions give off of present in the flame test for metal ions ?

Red flame

2

What colour flame would be given off when Na+ ions are present in sample?

Yellow

3

What colour would K+ give off in the flame test for metal ions?

Lilac

4

What colour flame would Ca2+ give off in the flame test?

Orange/red

5

What colour flame would be given off by Cu2+ in the flame test for metal ions ?

Blue/green

6

Describe the method for the flame test - for metal ions...

Firstly dip the wire loop into hydrochloride acid to remove impurities.Place loop in sample and that into outer blue flame of Bunsen burner

7

2 methods to test for metal ions ?

Flame test and Cation test

8

What colour is the precipitate formed from Al3+?

White, however it redissolves with excess NaOH to become colourless.

9

What colour is the precipitate of Ca2+ with NaOH?

White

10

What colour is the precipitate of Cu2+?

Blue precipitate

11

What colour is the precipitate of Fe2+?

Green precipitate

12

What colour is the precipitate formed from Fe3+ ?

Red or brown

13

Method to form a coloured precipitate ?

Take a small sample of solution and test it drop wise with sodium hydroxide(NaOH)

14

What do you add to form a coloured precipitate ?

Sodium Hydroxide (NaOH)

15

Test for Ammonium Ions ?

Add sodium hydroxide solution, then heat and test if the gas given off is the ammonia gas. We can heck that by placing a red damp Lito is paper over the gas and if it turns blue then it contains ammonium ions..

16

What are the anion tests ?

Tests for halide, carbonates
and sulfate ions.

17

What are the halide ions?

Bromide, iodide and chloride

18

What is the method for the halide test?

1. To solution add nitric acid
2. Add silver nitrate
3. Watch the colour change of the precipitate

19

What colour is the chloride precipitate?

White

20

What is the chemical formula when chloride undergoes a halide year?

Ag+ + Cl- = AgBr

21

What colour is the precipitate of bromide after a halide test?

Cream precipitate

22

What is the formula of bromide precipitate after it undergoes a halide test?

Br- + Ag+ = AgBr

23

What is the formula of iodide after a halide test?

Ag+ + I- = AgI

24

What colour is the precipitate of iodide after it undergoes the halide test?

Yellow

25

What is the method for the Carbonate test?

1. Add a dilute acid
2. If carbonates are present solution will fizz or bubble

26

What is the formula after a test for carbonates ?

Co2- + 2H+ = Co2 + H2O

27

How else can we check if carbon dioxide is given off in the carbonate test?

Use limewater , when CO2 present it will become milky

28

What is the method for the sulfates test?

1. Add hydrochloric acid
2. Add barium chloride.
3. Check if the solution turns white, this means sulfates are present

29

Formula after the test for sulfates ?

Ba2+ + SO(4)2- = BaSo4

30

What is the general formula for alcohols ?

Cn + H2n+1 OH

31

What happens to alcohols when they’re oxidised?

They become carboxylic acids

32

Example of an alcohol?

Methanol
Ethanol
Propanol
Butanol
Pentanol

33

What functional group are alcohols a part of ?

OH-

34

What is the general formula for carboxylic acids ?

Cn-1 + H2n-1 COOH

35

What are alkenes?

A homologous series of unsaturated hydrocarbons with a C=C functional group

36

What are alkanes?

A homologous series of saturated hydrocarbons.