Practice MCQ Questions and answers on General Science-GK

The working of Quartz is usually by a crystal oscillator. The Silicon dioxides are the crystals which are piezoelectric and can be further used as speakers and microphones.

Greenhouse gases include: Water vapour (H₂O), Carbon dioxide (CO₂), Methane (CH₄), Nitrous oxide (N₂O), Ozone (O₃), and Fluorinated gases such as CFCs, HFCs, PFCs, and SF₆.

Hydrogen (H₂) is not a greenhouse gas because it has no permanent electric dipole moment and therefore does not absorb infrared (IR) radiation effectively. The greenhouse effect occurs when gases absorb and re-emit infrared radiation emitted by Earth’s surface. Since hydrogen cannot interact with IR radiation in this way, it does not contribute to atmospheric warming.

Furthermore, hydrogen is a very light gas that tends to escape into the upper atmosphere, preventing its accumulation in significant amounts to influence Earth’s temperature.

Bromine (Br), chemical element, a deep red noxious liquid, and a member of the halogen elements, or Group 17 (Group VIIa) of the periodic table.

Diamond is regarded to be the hardest known material in the world.

The variety of coal in which the deposit contains recognizable traces of the original plant material is peat.

Tetraethyl lead is used as Petrol Additive.

Graphite is structurally composed of planes of polycyclic carbon atoms that are hexagonal in orientation. The distance of carbon atoms between planes is longer and therefore the bonding is weaker. Graphite is best suited for lubrication in air.
It is a mineral made of loosely bonded sheets of carbon atoms, giving it a slippery texture that makes it a very effective lubricant. This slippery quality also makes graphite a good material for pencil lead because it easily sloughs off onto paper.
Graphite is bonded by covalent bond, thus, it is helf by weak intermolecular forces. Since it has weak intermolecular forces, graphite would be slippery and soft enough to act as a lubricant.

The inert gas which is substituted for nitrogen in the air used by deep sea divers for breathing, is Helium.

The gases used in different types of welding would include Oxygen and Acetylene.

Deliquescence, the process by which a substance absorbs moisture from the atmosphere until it dissolves in the absorbed water and forms a solution.