Question 1

The chemical formula for Sulfuric Acid is:

Accepted Answer

Correct Answer: H2SO4

Explanation: Sulfuric Acid is a strong mineral acid with the formula H2SO4. It is an odorless, colorless to slightly yellow viscous liquid that is soluble in water. It is one of the most important industrial chemicals, used in the manufacture of fertilizers, explosives, car batteries, and chemical synthesis.

Question 2

In the computer world, 1 Kilobyte (KB) is equal to:

Accepted Answer

Correct Answer: 1024 Bytes

Explanation: In computing, 1 Kilobyte (KB) is traditionally equal to 1024 bytes. This is because computers use the binary system (base 2), and 2 to the power of 10 is 1024. While sometimes in decimal contexts (like hard drive marketing) 1000 is used, in memory and operating system contexts, 1024 is the standard measurement.

Question 3

The concept of Gravity was discovered by:

Accepted Answer

Correct Answer: Isaac Newton

Explanation: Isaac Newton is credited with formulating the law of universal gravitation. Legend has it that he was inspired by watching an apple fall from a tree, leading him to wonder if the same force that pulled the apple to Earth also kept the Moon in orbit. He published his work in the 'Principia Mathematica' in 1687.

Question 4

Which Vitamin is also known as Ascorbic Acid?

Accepted Answer

Correct Answer: Vitamin C

Explanation: Vitamin C is chemically known as Ascorbic Acid. It is a powerful antioxidant that helps protect cells from damage. It is vital for the growth, development, and repair of all body tissues. It plays a role in collagen formation, absorption of iron, and the immune system. Citrus fruits are famous sources.

Question 5

Which of the following is a non-renewable energy source?

Accepted Answer

Correct Answer: Coal

Explanation: Coal is a non-renewable energy source because it takes millions of years to form from the remains of ancient plants. Once we burn coal, it is gone forever and cannot be replenished within a human timescale. Burning coal also releases significant amounts of carbon dioxide and pollutants.

Question 6

The main component of Biogas is:

Accepted Answer

Correct Answer: Methane

Explanation: Biogas is primarily composed of Methane (50-75%) and Carbon Dioxide. It is produced by the breakdown of organic matter (like agricultural waste, manure, municipal waste) in the absence of oxygen. Methane is combustible, which makes biogas a valuable renewable energy source.

Question 7

Which gas is evolved when plants perform photosynthesis?

Accepted Answer

Correct Answer: Oxygen

Explanation: During photosynthesis, plants take in carbon dioxide and water to produce glucose and Oxygen. Oxygen is released as a byproduct into the atmosphere. This process is critical for aerobic life on Earth, as animals and humans need this oxygen to breathe. Effectively, plants act as the lungs of the planet.

Question 8

The SI unit of Force is:

Accepted Answer

Correct Answer: Newton

Explanation: The SI unit of force is the Newton (symbol: N), named after Sir Isaac Newton. One newton is the force needed to accelerate one kilogram of mass at the rate of one meter per second squared. It is a derived unit that relates force to mass and acceleration (F=ma).

Question 9

Which part of the eye controls the amount of light entering it?

Accepted Answer

Correct Answer: Iris

Explanation: The Iris is the colored part of the eye that controls the diameter and size of the pupil, and thus the amount of light reaching the retina. In bright light, the iris constricts the pupil to let in less light. In dim light, the iris dilates the pupil to allow more light to enter.

Question 10

The device used to convert Alternating Current (AC) to Direct Current (DC) is called:

Accepted Answer

Correct Answer: Rectifier

Explanation: A Rectifier is an electrical device that converts Alternating Current (AC), which periodically reverses direction, to Direct Current (DC), which flows in only one direction. Rectifiers are used in power supplies for radio, television, and computer equipment, as most electronics require DC power to function.

Question 11

CNG stands for:

Accepted Answer

Correct Answer: Compressed Natural Gas

Explanation: CNG stands for Compressed Natural Gas. It is a fuel that can be used in place of gasoline, diesel fuel, and LPG. CNG combustion produces fewer undesirable gases than the aforementioned fuels. It is made by compressing natural gas (which is mainly methane) to less than 1% of its standard volume.

Question 12

Which planet is known as the Blue Planet?

Accepted Answer

Correct Answer: Earth

Explanation: Earth is called the Blue Planet because about 71% of its surface is covered with water. From space, the oceans give the planet a dominant blue appearance. It is the only known planet in the universe that supports life. The presence of liquid water is a key factor that makes life possible here.

Question 13

The filament of an electric bulb is made of:

Accepted Answer

Correct Answer: Tungsten

Explanation: The filament of an electric bulb is made of Tungsten. This metal is chosen because it has the highest melting point of all pure metals (3,422°C). This allows the filament to become white-hot and emit light without melting. It also has a low rate of evaporation at high temperatures.

Question 14

Which disease is caused by the bite of the female Anopheles mosquito?

Accepted Answer

Correct Answer: Malaria

Explanation: Malaria is a life-threatening disease caused by parasites that are transmitted to people through the bites of infected female Anopheles mosquitoes. The parasites multiply in the liver and then infect red blood cells. Symptoms include fever, headache, and chills. It is preventable and curable.

Question 15

Sound travels fastest in:

Accepted Answer

Correct Answer: Solids (Steel)

Explanation: Sound travels fastest through solids, such as steel. This is because the molecules in solids are packed tightly together, allowing the sound waves (vibrations) to pass from one molecule to another very quickly. In contrast, sound travels slower in liquids and slowest in gases (air). Sound cannot travel in a vacuum.

Question 16

The largest organ in the human body is:

Accepted Answer

Correct Answer: Skin

Explanation: The Skin is the largest organ of the human body. It acts as a protective barrier against the external environment, preventing the entry of pathogens and preventing dehydration. It also plays a key role in regulating body temperature and sensation. The liver is the largest internal organ, but the skin covers the entire external surface.

Question 17

Which Vitamin is produced by the body when exposed to Sunlight?

Accepted Answer

Correct Answer: Vitamin D

Explanation: Vitamin D is unique because the body can synthesize it when sunlight hits the skin. Specifically, UV rays from the sun convert a chemical in the skin into an active form of Vitamin D (calciferol). It is crucial for the absorption of calcium and phosphorus, which are vital for healthy bones and teeth.

Question 18

The boiling point of water on the Celsius scale is:

Accepted Answer

Correct Answer: 100°C

Explanation: The boiling point of water is 100 degrees Celsius at standard atmospheric pressure (sea level). At this temperature, the vapor pressure of the liquid equals the pressure surrounding the liquid, and the liquid changes into a vapor (gas). The boiling point decreases at higher altitudes because the atmospheric pressure is lower.

Question 19

Which gas is known as Laughing Gas?

Accepted Answer

Correct Answer: Nitrous Oxide

Explanation: Nitrous Oxide (N2O) is commonly known as Laughing Gas. It is a colorless gas with a slightly sweet scent and taste. It is used in surgery and dentistry for its anaesthetic and analgesic effects. When inhaled, it can induce a state of euphoria or laughter, hence the name. It is also used in vehicle engines.

Question 20

What is the chemical symbol for Gold?

Accepted Answer

Correct Answer: Au

Explanation: The chemical symbol for Gold is 'Au', which comes from the Latin word 'Aurum', meaning 'shining dawn'. Gold is a precious metal known for its malleability, ductility, and resistance to corrosion. It has been used for coinage, jewelry, and art throughout recorded history. It is also an excellent conductor of electricity.

Everyday Science MCQs