Island School Chemistry
A&A 9c
Preparation & Analysis Questions ANSWERS
1. Identify each of the following substances by identifying both the positive and
negative ions present. The first one has been done for you.
CATION (+ ION) test
A
Yellow flame test
B
Sodium ions ( Na+)
Lilac flame test
ANION (- ION) test
Name & formula
White precipitate with
silver nitrate
Chloride ions (Cl -)
White precipitate with
barium chloride
Sodium chloride
(NaCl)
Potassium sulfate
K2SO4
Copper(II) carbonate
CuCO3
C
Blue precipitate with
sodium hydroxide
Bubbles (of CO2) with
acid
D
Red flame test
Yellow precipitate with
silver nitrate
Lithium iodide
LiI
E
Green precipitate with
sodium hydroxide
Yellow precipitate with
silver nitrate
Iron(II) iodide
Fe I2
F
Brown precipitate with
sodium hydroxide
White precipitate with
barium chloride
Iron(III) sulfate
Fe2(SO4)3
G
Brick red flame test
White precipitate with
silver nitrate
Calcium chloride
CaCl2
H
Lilac flame test
Cream precipitate with
silver nitrate
Potassium bromide
KBr
I
Blue precipitate with
sodium hydroxide
solution
White precipitate with
barium chloride
Copper(II) sulfate
CuSO4
J
Produces an alkaline gas
when heated with
sodium hydroxide
Bubbles with acid
Ammonium carbonate
(NH4)2CO3
Island School Chemistry
A&A 9c
2. Give the tests that you would use to identify the positive and the negative ions in
each of the following substances. Also give the result of the test.
Formula
KCl
Test for cation
Flame test
Result
lilac
CaCO3
Flame test
Orange/red HCl (or any acid)
Fizz
CuSO4
NaOH
Blue ppt
Acidified BaCl2
white ppt
FeBr2
NaOH
Green ppt
Acidified AgNO3
cream ppt
Flame test
Bright red
Acidified AgNO3
yellow ppt
NaOH,
warm gently
and UI paper
UI blue
None!!!
Li I
NH4NO3
Test for anion
Acidified AgNO3
X
3. Identify the substances below:
What do I do?
I ‘pop’ with a lighted splint
Result
white ppt
What am I?
H2
I turn limewater milky
CO2
I smell awful and turn damp red litmus blue
NH3
I bleach damp indicator paper
Cl2
I turn anhydrous copper(II)sulphate from white to
blue
I relight a glowing splint
H2O
O2