ACIDS
Stomach
The stomach produces hydrochloric acid to help with digestion. The enzymes which break down food in the stomach work best in an acidic environment
Having acid in the stomach also helps to kill bacteria - making it less likely that you'll go down with some kind of food poisoning
Indigestion Remedies
Indigestion is cause by too much HCI in the stomach. Indigestion tablets contain bases such as calcium carbonate, which neutralise the excess acid.
Bases
Metal oxides and metal hydroxides are generally bases
This means they can be neutralised with acids to form a salt and water
Metal carbonates give salt + water + carbon dioxide
HCI produce chloride salts
Nitric acid produce nitrate salts
Sulfuric acid produce sulfate salts
Electrolysis
Electrolysis is the decomposition of a compound using electrical energy
The electricity comes from a direct current source such as a battery
It requires a liquid to conduct the electricity, called the electrolyte
The electricity is applied to the electrolyte by two electrodes
The electrolyte contains the compound, which is broken down into it component parts.
The components parts are released as atoms or molecules - often as gas
Tests
Chlorine bleaches damp litmus paper, turning it white. (It may turn red for a moment first though) - that's because a solution of chlorine is acidic).
Hydrogen makes a "squeaky pop" with a lighted splint
Chlorine
Sea water or brine (sodium chloride solution) can be decomposed by electrolysis.
It can be used to make chlorine gas
Chlorine gas is toxic - so this makes the manufacture of its hazardous process.
It's needed for the manufacture of bleach
it's used to make the polymer poly(chloroethene) - PVC
You can test for oxygen by checking if the gas relights a glowing splint