Chemistry Quiz 6

When copper is exposed to the atmosphere, it becomes coated with green carbonate. Copper when combined with oxygen in the air, forms oxide. Copper carbonate is formed when oxide reacts with CO₂, giving it a green tint.

Rusting is an oxidation reaction. The iron reacts with water and oxygen to form hydrated iron(III) oxide, which we see as rust. Hence, iron rust when they come into contact with water and oxygen – both are needed for rusting to occur.

Cement is formed by strongly heating a mixture of limestone and clay. Cement manufacturing is a complex process that begins with mining and then grinding raw materials that include limestone and clay, to a fine powder, called raw meal, which is then heated to a sintering temperature as high as 1450 °C in a cement kiln.

Diamond is harder than graphite because of tetrahedral structure of diamond. In a diamond, the carbon atoms are arranged tetrahedrally. Each carbon atom is attached to four other carbon atoms 1.544 × 10^-10 meter away with a C-C-C bond angle of 109.5 degrees. It is a strong, rigid three-dimensional structure that results in an infinite network of atoms.

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.

Hydrogen peroxide is an antiseptic frequently used to clean minor cuts or disinfect surfaces. Gargling with hydrogen peroxide may help treat minor mouth irritations, such as cuts or canker sores because it is an antiseptic. In fact, many types of toothpaste and mouthwash in stores already contain this compound.

Solar technologies convert sunlight into electrical energy either through photovoltaic (PV) panels or through mirrors that concentrate solar radiation. Silicon is the most common semiconductor material used in photovoltaic panels.

The reason there is not much hydrogen in the atmosphere is because it is lighter than air, and so can easily escape the Earth's gravity.

Historically, tannins extracted from oak galls were used for making ink by mixing them with iron compounds, such as iron(II) sulphate to form complex, water-soluble blue-black compounds.

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.