Sheet mica is used principally in the electronic and electrical industries. Its usefulness in these applications is derived from its unique electrical and thermal insulating properties and its mechanical properties, which allow it to be cut, punched, stamped, and machined to close tolerances. Specifically, Mica is unusual in that it is a good electrical insulator at the same time as being a good thermal conductor.

Correct Option: D

Sheet mica is used principally in the electronic and electrical industries. Its usefulness in these applications is derived from its unique electrical and thermal insulating properties and its mechanical properties, which allow it to be cut, punched, stamped, and machined to close tolerances. Specifically, Mica is unusual in that it is a good electrical insulator at the same time as being a good thermal conductor.

The term "coal is a black gold" is just a simple metaphor. Even today, we burn more coal than natural gas, more than nuclear, more than anything.

Correct Option: A

The term "coal is a black gold" is just a simple metaphor. Even today, we burn more coal than natural gas, more than nuclear, more than anything.

The mass number is a count of the number of particles in an atom's nucleus which is made up of protons and neutrons. In other words, Mass Number = Number of Protons + Number of Neutrons. The atomic number is the number of protons in an atom of an element, i.e., 226 = 88 + number of Neutrons. So, the number of neutrons= 226 – 88= 138.

Correct Option: B

The mass number is a count of the number of particles in an atom's nucleus which is made up of protons and neutrons. In other words, Mass Number = Number of Protons + Number of Neutrons. The atomic number is the number of protons in an atom of an element, i.e., 226 = 88 + number of Neutrons. So, the number of neutrons= 226 – 88= 138.

When quick lime is added to water, then a chemical reaction takes places and slaked lime is formed, evolving heat in this process. It makes the water boil. CaO + H₂O ® Ca(OH)₂ + heat

Correct Option: A

When quick lime is added to water, then a chemical reaction takes places and slaked lime is formed, evolving heat in this process. It makes the water boil. CaO + H₂O ® Ca(OH)₂ + heat

Sodium chloride, also known as salt, common salt, table salt or halite, is an ionic compound with the formula NaCl, representing equal proportions of sodium and chloride. Sodium chloride is the salt most responsible for the salinity of the ocean and of the extracellular fluid of many multi-cellular organisms.

Correct Option: C

Sodium chloride, also known as salt, common salt, table salt or halite, is an ionic compound with the formula NaCl, representing equal proportions of sodium and chloride. Sodium chloride is the salt most responsible for the salinity of the ocean and of the extracellular fluid of many multi-cellular organisms.