Chemical tests

Created by

abhinav

Cards (22)

Test for chlorine gas
Turns damp blue litmus paper white
Test for oxygen gas
Causes glowing splint to relight
Test for hydrogen gas
Causes a burning splint to make a squeaky pop noise
Test for carbon dioxide gas
Bubble through limewater and causes it to turn cloudy
Test for ammonia gas
Turns damp red litmus paper blue
How to carry out flame tests?
Dip the loop of an unreactive metal into a dilute acid and then hold to the flame of a bunsen burner to decontaminate it. Then dip the loop in the sample and hold to a blue bunsen burner flame.
Colour of lithium in flame test
Red
Colour of sodium in flame test
Yellow
Colour of pottasium in flame test
Lilac
Colour of calcium in flame test
Orange - red
Colour of copper in flame test
blue - green
How can cattions (positive ions) be tested for? 
They can be identified by the colour of the precipitate they form when reacted with sodium hydroxide
Cu2+ - Copper(II)
light blue precipitate
Fe2+ - Iron(II)
green precipitate
Fe3+ - Iron(III)
Red - brown precipitate
How are carbonates tested ?
Add dilute hydrochloric acid and test the gas released using limewater test, which turns cloudy
How are sulfates tested for ?
Add dilute hydrochloric acid to remove impurities. Then react with barium chloride. Positive test will form white precipitate
How are halides tested for ?
Add dilute nitric acid to remove impurities. Then react with silver nitrate.
Positive test for chlorides?
White precipitate
Positive test for bromides?
Cream precipitate
Positive test for iodides?
Yellow precipitate
How do you test for water?
Add anhydrous copper(II) sulfate. Turns white to blue if positive for water.