[13] Chemical tests

What is the test for hydrogen gas?

lit splint squeaky pop

What is the test for oxygen gas?

glowing split relights

What is the test for carbon dioxide gas?

Bubble the gas through limewater; if it turns cloudy, carbon dioxide is present.

What is the test for ammonium ions?

Add sodium hydroxide and hold damp red litmus paper over the gas given off; if it turns blue ammonium ions are present

How do you carry out a flame test?

1. Clean a wire loop in hydrochloric acid and rinse in distilled water

2. Dip the loop into the sample and place it in a blue Bunsen burner flame.

What color flame does lithium produce in a flame test?

red

What color flame does sodium produce in a flame test?

yellow

What color flame does potassium produce in a flame test?

lilac

What color flame does calcium produce in a flame test?

orange-red

What how do you test for copper (ii) ions not adding something

flame test, Blue-green colour

How do you test for copper (II) ions (Cu²⁺) other than the flame test

Add sodium hydroxide solution, blue precipitate forms

How do you test for iron (II) ions (Fe²⁺) using sodium hydroxide?

Add sodium hydroxide solution a green precipitate forms

How do you test for iron (III) ions

Add sodium hydroxide solution an orange brown precipitate forms

How do you test for the halides:
chloride ions
bromide ions
iodide ions

Add dilute nitric acid and then dilute silver nitrate solution
Chloride will form a White precipitate
Bromide will form a Cream precipitate
Iodide will form a Yellow precipitate

How do you test for sulfate ions

Add dilute hydrochloric acid then barium chloride a white precipitate will form

How do you test for carbonate ions

Add hydrochloric acid and bubble gas through limewater a while precipitate will form

How do you test for the presence of water

Add anhydrous copper(II) sulfate it should turn from white to blue

what is the mass on an electron

0.0005

what percentage of air is argon

0.93%

what percentage of the air is carbon dioxide

0.04%

which 2 main gases dissolve to cause acid rain

sulfur dioxide and nitrogen dioxide

what is seen when copper carbonate decomposes

green powder (CuCO₃ )
black poder (CuO)