Chemistry Quiz 2

When a helium atom loses an electron it becomes a positive helium ion. When an atom gains/loses an electron, the atom becomes charged, and is called an ion. If a neutral atom gains an electron, it becomes negative. This kind of ion is called an anion. If a neutral atom loses an electron, it becomes positive. This kind of ion is called a cation.

Oxalic acid is manufactured using sawdust. The heating of sawdust with Potassium hydroxide (KOH) results in the production of oxalic acid.

Radioactive disintegration of uranium ultimately results in formation of lead. The half-life of uranium-238 is 4.5 billion years. It decays into radium-226, which in turn decays into radon-222. Radon-222 becomes polonium-210, which finally decays into a stable nuclide, lead.

The metal, which is a constituent of vitamin B₁₂ is Cobalt. Cyanocobalamin (commonly known as Vitamin B₁₂) is a highly complex, essential vitamin, owing its name to the fact that it contains the mineral, cobalt.

If there is no carbon dioxide (CO₂) in the earth's atmosphere, the temperature of the earth's surface would be less than the present. CO₂ is an important greenhouse gas that helps to trap heat in our atmosphere. Without it, our planet would be very cold.

Petrol has the least density among the given liquids. Mercury has a density of 13545.848 kg/m³, which is about 13.5 times denser than water (1000 kg/m³). Water is denser than petrol (800 kg/m³)

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.

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.

The tip of the match-stick is made of an oxidizing agent such as potassium chlorate, mixed with sulphur, fillers and glass powder. The side of the box contains red phosphorus, binder and powdered glass.

Glass is a supercooled liquid. Supercooling is the process of lowering the temperature of a liquid or a gas below its freezing point without it becoming a solid. It achieves this in the absence of a seed crystal or nucleus around which a crystal structure can form.