Showing 41–50 of 419 questions
Q.41
Easy
General Science
What is the chemical formula for table salt?
A
NaCl
B
KCl
C
CaCl₂
D
MgCl₂
Explanation:
Table salt is sodium chloride (NaCl), composed of sodium and chlorine ions in a 1:1 ratio.
Q.42
Easy
General Science
Which vitamin is produced by the skin when exposed to sunlight?
A
Vitamin A
B
Vitamin B
C
Vitamin D
D
Vitamin E
Correct Answer:
C. Vitamin D
Explanation:
Vitamin D is synthesized in the skin upon exposure to ultraviolet (UV) radiation from sunlight.
Q.43
Easy
General Science
Which element has the atomic number 6?
A
Oxygen
B
Nitrogen
C
Carbon
D
Helium
Correct Answer:
C. Carbon
Explanation:
Carbon has atomic number 6, meaning it has 6 protons in its nucleus. It is the basis of all organic compounds.
Q.44
Medium
General Science
Which organ in the human body produces insulin?
A
Liver
B
Pancreas
C
Kidney
D
Stomach
Correct Answer:
B. Pancreas
Explanation:
The pancreas produces insulin, a hormone that regulates blood glucose levels. The beta cells in the pancreas secrete this hormone.
Q.45
Medium
General Science
Which of the following is a renewable energy source?
A
Coal
B
Petroleum
C
Solar energy
D
Natural gas
Correct Answer:
C. Solar energy
Explanation:
Solar energy is renewable as the sun's energy is continuously available. Coal, petroleum, and natural gas are non-renewable fossil fuels.
Q.46
Easy
General Science
What is the boiling point of water at standard atmospheric pressure?
A
90°C
B
100°C
C
110°C
D
80°C
Explanation:
Water boils at 100°C (212°F) at standard atmospheric pressure of 1 atm or 101.325 kPa.
Q.47
Medium
General Science
Which blood group is considered a universal recipient?
Explanation:
AB blood group is the universal recipient because it has both A and B antigens, allowing it to receive blood from all groups.
Q.48
Medium
General Science
Which element is the most abundant in the Earth's atmosphere?
A
Oxygen
B
Nitrogen
C
Argon
D
Carbon dioxide
Correct Answer:
B. Nitrogen
Explanation:
Nitrogen comprises about 78% of Earth's atmosphere, followed by oxygen at about 21%.
Q.49
Medium
General Science
What is the principal source of energy for the Earth?
A
The Moon
B
The Sun
C
Geothermal energy
D
Nuclear reactions in Earth's core
Correct Answer:
B. The Sun
Explanation:
The Sun is the primary source of energy for Earth, providing energy through radiation that drives weather, climate, and photosynthesis.
Q.50
Medium
General Science
Which of the following is an example of a physical change?
A
Rusting of iron
B
Burning of paper
C
Melting of ice
D
Digestion of food
Correct Answer:
C. Melting of ice
Explanation:
Melting of ice is a physical change as water remains H₂O but changes from solid to liquid state. Other options are chemical changes.
