Thanks, your questions seem very realistic.
I'll post up the questions I have for C5;
1. What is the concentration of salts in the sea?
81/3
2. How would the concentration of salts in the lake have changed over the past 30 years? Explain your prediction.
They would have increased due to increased evaporation of water.
3. Write down the formaula of salt formed from Sulphric Acid (Can someone help me on this question)
sulhpuric acid + what? Why do you need to know this?
4. What gas will be released when the acid reacts with the tufa towers?
Carbon dioxide.
5. In the past the towers were broken up local farmers and spread onto thier land to improve its fertility. What affect would the addition of the powder have on the soil's pH?
Make it more alkaline I suppose.
6. Why is it likely that towers like this would ever form in England?
Not many hot springs, not that hot - not much evaporation of water, lots of rain - make it overflow.
7. When salt crystals form at the edges of the lake, why are the ions attracted to echother?
I guess it's because the opposite charges of the ions are attracted to one another.
8. how grams of salt will be in 1dm^3 of sea water?
81/3
9. If some acid was dropped onto some tufa what would you see?
Depends on concentration - strong acid would cause a reaction in which there would be lots of fizzing, some tufa would obviousily be dissolved and you CO2 would be given off.
10. Sulhuric acid is in acid rain. How is it made?