1
Q
What is method 1?
A
- use a measuring cylinder to measure 25cm^3 of sulphuric acid
- pour the acid into a beaker
- set up Bunsen burner, tripod and gauze and heat the acid gently- do not let it boil
- turn off the Bunsen burner
- remove the beaker from the gauze and put on the heat-proof mat
- add magnesium and wait for it to stop reacting
- continue to add magnesium until no more will react
- filter off excess metal, collecting the filtrate in a evaporating basin
- heat the evaporating basin, do not boil until crystals appear on the edge
- leave the evaporating basin to cool and allow crystals to form
- filter out the crystals and dry on paper towel
2
Q
Method 1:Why is it important that you put the Bunsen burner out before you start adding the magnesium to the acid?
A
You’re producing hydrogen gas and it’s flammable
3
Q
Method 1:Why did you heat up the sulphuric acid?
A
To speed up the rate of the reaction
4
Q
Method 1:What two observations indicated that the magnesium had finished reacting?
A
It stopped fizzing, stopped producing hydrogen(no more bubbles), magnesium doesn’t dissolve
