IGCSE CHEMISTRY: TESTING FOR IONS.
Trusted by students across multiple disciplines!
A gas is bubbled through limewater and the limewater goes cloudy. Identify the gas. -
Answer: Carbon dioxide
Describe the test for ammonia gas - Answer: Turns damp red litmus paper blue
Describe the test for carbon dioxide gas - Answer: Bubble the gas through limewater
and see if it goes cloudy
Describe the test for chlorine gas - Answer: Turns moist litmus paper white (bleaches)
Describe the test for hydrogen gas - Answer: Use a lit splint to see if the gas pops
Describe the test for oxygen gas - Answer: Use a glowing splint and see if it relights
In the test of a gas, a glowing splint relights. What is the gas? - Answer: Oxygen
In the test of a gas, a lit splint gives a squeaky pop. What is the gas? - Answer:
Hydrogen
Which gas will bleach moist litmus paper? - Answer: Chlorine
Which gas will turn damp red litmus paper blue? - Answer: Ammonia
Describe how you would carry out a flame test - Answer: Put solid onto a wire. Put into
a blue flame
In a flame test, why is hydrochloric acid used? - Answer: To clean the wire of any
unwanted ions
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APPHIA - Crafted with Care and Precision for Academic Excellence.
, How are calcium ions identified, and what is the result? - Answer: Using a flame test.
Flame colour is orange- red
How are lithium ions identified, and what is the result? - Answer: Using a flame test.
Flame colour is red
How are potassium ions identified, and what is the result? - Answer: Using a flame test.
Flame colour is lilac
How are sodium ions identified, and what is the result? - Answer: Using a flame test.
Flame colour is yellow
In a flame test, a blue-green colour is seen. Give the formula of the cation which is
present. - Answer: Cu²⁺
In a flame test, a orange-red colour is seen. Give the formula of the cation which is
present. - Answer: Ca²⁺
In a flame test, a red colour is seen. Give the formula of the cation which is present. -
Answer: Li⁺
In a flame test, a lilac colour is seen. Give the formula of the cation which is present. -
Answer: K⁺
In a flame test, a yellow colour is seen. Give the formula of the cation which is present. -
Answer: Na⁺
In the flame test for copper (II) ions what colour is the result? - Answer: Blue-green
Give the name of the blue precipitate formed when sodium hydroxide is added to a
solution containing Cu²⁺ - Answer: copper (II) hydroxide
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APPHIA - Crafted with Care and Precision for Academic Excellence.
Trusted by students across multiple disciplines!
A gas is bubbled through limewater and the limewater goes cloudy. Identify the gas. -
Answer: Carbon dioxide
Describe the test for ammonia gas - Answer: Turns damp red litmus paper blue
Describe the test for carbon dioxide gas - Answer: Bubble the gas through limewater
and see if it goes cloudy
Describe the test for chlorine gas - Answer: Turns moist litmus paper white (bleaches)
Describe the test for hydrogen gas - Answer: Use a lit splint to see if the gas pops
Describe the test for oxygen gas - Answer: Use a glowing splint and see if it relights
In the test of a gas, a glowing splint relights. What is the gas? - Answer: Oxygen
In the test of a gas, a lit splint gives a squeaky pop. What is the gas? - Answer:
Hydrogen
Which gas will bleach moist litmus paper? - Answer: Chlorine
Which gas will turn damp red litmus paper blue? - Answer: Ammonia
Describe how you would carry out a flame test - Answer: Put solid onto a wire. Put into
a blue flame
In a flame test, why is hydrochloric acid used? - Answer: To clean the wire of any
unwanted ions
1
APPHIA - Crafted with Care and Precision for Academic Excellence.
, How are calcium ions identified, and what is the result? - Answer: Using a flame test.
Flame colour is orange- red
How are lithium ions identified, and what is the result? - Answer: Using a flame test.
Flame colour is red
How are potassium ions identified, and what is the result? - Answer: Using a flame test.
Flame colour is lilac
How are sodium ions identified, and what is the result? - Answer: Using a flame test.
Flame colour is yellow
In a flame test, a blue-green colour is seen. Give the formula of the cation which is
present. - Answer: Cu²⁺
In a flame test, a orange-red colour is seen. Give the formula of the cation which is
present. - Answer: Ca²⁺
In a flame test, a red colour is seen. Give the formula of the cation which is present. -
Answer: Li⁺
In a flame test, a lilac colour is seen. Give the formula of the cation which is present. -
Answer: K⁺
In a flame test, a yellow colour is seen. Give the formula of the cation which is present. -
Answer: Na⁺
In the flame test for copper (II) ions what colour is the result? - Answer: Blue-green
Give the name of the blue precipitate formed when sodium hydroxide is added to a
solution containing Cu²⁺ - Answer: copper (II) hydroxide
2
APPHIA - Crafted with Care and Precision for Academic Excellence.
