Acids

Below are links for Topic 3:

Indigestion

Indigestion Remedies PCA

Neutralisation

Electrolysis PCA

The Importance of Chlorine

Electrolysis of Water

What you should know:

• 3.1 Know that hydrochloric acid is produced in the stomach to:
  • a) help digestion
  • b) kill bacteria
• 3.2 Be able to describe indigestion remedies as containing substances that neutralise excess stomach acid.
• 3.3 Revise the investigation (hopefully you did) into the effectiveness of different indigestion remedies.
  • This involves titrating the alkaline crushed tablets in water with a standard solution of alkali.
• 3.4 Know that acids are neutralised by:
  • a) metal oxides
  • b) metal hydroxides
  • c) metal carbonates to produce salts
  • (note that no details of salt preparation techniques or ions are required here)
• 3.5 Know that:
  • a) hydrochloric acid produces chloride salts
  • b) nitric acid produces nitrate salts
  • c) sulfuric acid produces sulfate salts (old names sulphuric acid and sulphates)
• 3.6 Be able to describe electrolysis as a process in which electrical energy, from a d.c. supply, decomposes compounds.
  • You should be familiar with the electrolysis of dilute hydrochloric acid to produce hydrogen and chlorine.
  • (Note that explanations of the reactions at the electrodes are not required)
• 3.7 You should know how to investigate the electrolysis of dilute hydrochloric acid and the products formed.
• 3.8 Be able to describe the chemical test for hydrogen.
• 3.9 Be able to describe the chemical test for chlorine.
• 3.10 Know that chlorine can be obtained from sea water by electrolysis.
  • (Note that explanations of the reactions at the electrodes are not required)
• 3.11 Know that chlorine as a toxic gas and that this leads to potential hazards associated with its large-scale manufacture.
  • 
• 3.12 Be able to describe the use of chlorine in the manufacture of bleach and of the polymer poly(chloroethene) (PVC).
• 3.13 Know that water can be decomposed by electrolysis to form hydrogen and oxygen (by electrolysis of dilute sulfuric acid solution).
• 3.14 Be able to describe the chemical test for oxygen.