Climate Change + Chemical Tests Flashcards
What is the greenhouse effect?
The greenhouse effect is natural - It is when UV energy from the sun enters the atmsphere, some gets trapped and warms up the earth, some goes off into space.
What in the atmosphere blocks harmful UV light from the sun?
Ozone (O3)
How can you test the volume of oxygen in air?
Have a conical with air and an excess of wet iron or copper filings, with a gas syringe connected. The oxygen will react with the iron/copper to make iron/copper oxide, the syringe will go down from 100cm^3 to about 79cm^3, (the amount of oxygen in air, 21% or1/5)
What are the tests for: (Include the positive result)
Water (there are 2)
Ammonia (2)
Hydrogen (1)
Oxygen (1)
Chlorine (1)
Carbon Dioxide (1)
Pure water (2 steps)
Water 1- Anhydrus copper sulphate (Positive result is white -> blue)
Water 2 - Cobalt chloride paper (Blue -> Pink)
Ammonia 1 - Damp red litmus paper (Red -> Blue)
Ammonia 2 - Put near HCL (White smoke)
Hydrogen - Lit splint (Squeaky pop)
Oxygen - Glowing splint (Relights)
Chlorine - Damp red litmus paper (Red litmus paper bleaches to white)
Carbon Dioxide - Bubble through limewater (Milky white precipitate)
Pure Water - Boils at 100C and Freezes at 0C
What are the flame tests for:
Lithium
Calcium
Copper
Potassium
Sodium
Li - Crimson Red
Ca - Brick Red
Cu - Blue-green
K - Lilac
Na - Yellow-orange
How do you do a halide test? What are the positive results for:
Chlorine
Bromine
Iodine
To do a halide test you add silver nitrate (Ag NO3)
Cl - White precipitate
Br - Cream precipitate
I - Yellow precipitate
How do you test for:
A sulphate ion
A carbonate ion
Sulphate ion - Add HCL the barium chloride
Carbonate - Add HCL and bubble through limewater
What is the formula for:
Hydrochloric acid
Sulphuric acid
Nitric acid
HCL
H2 SO4
HNO3
How do you test for ammonium Ions
- Add sodium hydroxide (No reaction)
- Warm (Damp red litmus turns blue)
