SolutionsHome and Industry
1. From monomer to plastic
Give the monomer of: a) polyethylene; b) polypropylene; c) PVC; d) polystyrene.
- Ethylene (ethene), CH2=CH2.
- Propylene (propene), CH2=CHCH3.
- Vinyl chloride (chloroethene), CH2=CHCl.
- Styrene (vinylbenzene), CH2=CHC6H5.
2. Vinegar against limescale
Why does vinegar remove limescale from a tap? Write the reaction.
Acetic acid reacts with calcium carbonate (insoluble) to form calcium acetate, which is soluble, together with water and carbon dioxide:
2 CH3COOH + CaCO3 → (CH3COO)2Ca + H2O + CO2
3. Dangerous mixtures
Why must bleach never be mixed with an acidic descaler?
Because the acid reacts with the hypochlorite and releases chlorine gas, which is very toxic to breathe.