A reduction is a process in which electronegative atoms are removed. In chemistry, Reduction is a reaction that adds electrons to a substance.

Litmus is a water-soluble mixture of different dyes extracted from lichens. The main use of litmus is to test whether a solution is acidic or basic. Blue litmus paper turns red under acidic conditions, and red litmus paper turns blue under basic or caustic conditions.

Hydrochloric acid is used in combination with nitric acid to form a mixture called aqua regia. Aqua regia is a highly corrosive and effective mixture used to dissolve gold and platinum, which are resistant to single acids. The nitric acid acts as an oxidizing agent, while the hydrochloric acid provides chloride ions that form soluble complexes with gold, enabling its extraction.

Lead-acid battery is a type of rechargeable electrochemical battery storage available. 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. As the battery charges, the sulfuric acid reacts with the lead in the anode and cathode to produce electric power.

A dry cell is a type of electric battery, commonly used for portable electrical devices. A standard dry cell comprises a zinc anode, usually in the form of a cylindrical pot where an oxidation reaction occurs (loss of electrons for the electroactive species), with a carbon cathode in the form of a central rod where a reduction reaction occurs (gain of electrons for the electroactive species).

Soft water is free from dissolved salts, calcium, iron, or magnesium. This water can only be found from rain which is also called the highest natural sources of such water. Another way is to make it into lab-Distill water.

The electrical wire and cables shrink in cold weather and become loose in hot weather. If the wires are set tightly between the poles, in winter or cold weather the poles may bend or break due to contraction.

Helium is the hardest gas to liquefy because it has the lowest boiling point of all the elements at about 4.2 Kelvin (-268.9°C) under atmospheric pressure. This is due to its weak intermolecular forces (van der Waals forces), as it is a noble gas with a fully filled electron shell, making it chemically inert and nonpolar.

To liquefy helium, extremely low temperatures and high pressures are required. Even then, helium remains a quantum mechanical substance, and below 2.17 Kelvin, it forms a superfluid state (liquid helium-II) with unique properties like zero viscosity.

Nitrogen is used in incandescent bulbs to prevent the tungsten filament from oxidizing at high temperatures. It is an inert and cost-effective gas that reduces filament evaporation, prolonging the bulb's life. Sometimes, it is mixed with argon for better performance.

Argon gas is used in fluorescent and incandescent light lights to create an inert atmosphere inside the light. Argon is heavy (compared to neon or helium) which allows for more deposition of energy within the gas. This increases the detector's efficiency.