Chemistry Quiz 3

The polymerisation of ethylene is used in the manufacturing of polythene in industry. Polyethylene (also called polythene) is made through an addition polymerization reaction that utilizes an ethylene monomer (–C₂H₄–) repeated along the chain.

Potassium permanganate (KMnO₄) is used for purifying drinking water because it is a strong oxidsing agent. It oxidises dissolved iron, manganese, and hydrogen sulfide into solid particles that are filtered out of the water. This is the reason why it is used as a cleansing agent.

Copper sulphate (CuSO₄) is used for destroying Fungi in water tanks. It can kill bacteria, algae, roots, plants, snails and fungi.

Oxygen is by far the most abundant element in the Earth's crust, making up 46% of mass. This is due to oxygen being a very common rock-forming element together with silicon (28%). Other common elements are aluminium (8.2%), iron (5.6%), calcium (4.2%), sodium (2.5%), magnesium (2.4%), potassium, (2.0%). Making aluminium the most common metal in the crust.

Detergent is a sodium salt of long-chain benzene sulphonic acid or sodium salt of long-chain alkyl hydrogen sulphate, which has cleansing properties in water. Like soaps, Detergents contain anionic groups such as sulphonate groups or sulphate groups and long-chain hydrocarbon, a non-ionic group.

The chemical name of 'Common salt' is Sodium chloride. Sodium chloride is an ionic compound with the chemical formula NaCl, representing a 1:1 ratio of sodium (Na⁺) and chloride (Cl^–) ions.

Cement in different types is made mainly by calcining a mixture of about 75% limestone and 25% clay to form a calcium silicate clinker which is then ground and mixed with a small amount of gypsum.

The long-range potential of nuclear energy in India depends on its reserves of uranium. As of November 2020, 22 reactors – 7382 MWe (gross) – of nuclear capacity were fuelled by indigenous uranium and being operated close to their rated capacity.

In a lead-acid battery, the cathode is made of lead dioxide, and the anode is made of metallic lead. The two electrodes are separated by an electrolyte of sulfuric acid. Here, lead dioxide, lead metal, and sulfuric acid react to form lead sulphate and water; the separate processes are the oxidation of lead to lead sulphate at one electrode and the reduction of lead dioxide to lead sulphate at the other while the electric charge is transported through the electrolyte by the migration of hydrogen ions.

Phenol is widely used in the plastic industry for manufacturing bakelite. The chemical name of Bakelite is Polyoxybenzylmethylenglycolanhydride, (C₆H₆O·CH₂O)_n. It is a polymer made up of the monomers phenol and formaldehyde. This phenol-formaldehyde resin is a thermosetting polymer.