Chemistry MCQs
Our Chemistry MCQs section is tailored for students and job seekers aiming for excellence in academic and competitive exams. It includes a vast selection of multiple-choice questions covering organic chemistry, inorganic chemistry, analytical chemistry, physical chemistry, and biochemistry. These MCQs are suitable for FSc, BSc, pre-medical, and pre-engineering students, as well as CSS, PMS, NTS, and other competitive exams in Pakistan. Designed by subject experts, the questions help reinforce key concepts, test analytical skills, and improve speed and accuracy. Each topic includes beginner to advanced-level questions with a focus on the latest syllabus and past papers. If you are preparing for university entry tests or government job recruitment exams, this resource offers an excellent opportunity to master chemistry topics effectively.
Q: Which acid is used in car batteries?
A) Sulfuric acid
B) Nitric acid
C) Acetic acid
D) Hydrochloric acid
✅ Correct Answer: A
Explanation: Lead-acid batteries contain sulfuric acid.
Q: The most abundant element in Earth’s crust is:
A) Oxygen
B) Iron
C) Silicon
D) Calcium
✅ Correct Answer: A
Explanation: Oxygen makes up about 46% of Earth’s crust by weight.
Q: During electrolysis of water, the gas collected at the cathode is:
A) Oxygen
B) Hydrogen
C) Nitrogen
D) Carbon dioxide
✅ Correct Answer: B
Explanation: Hydrogen is released at the negatively charged electrode.
Q: Which color indicates a strong base on universal indicator?
A) Blue
B) Purple
C) Red
D) Green
✅ Correct Answer: B
Explanation: Strong bases turn indicators dark purple.
Q: Bleaching powder is chemically known as:
A) Calcium oxychloride
B) Calcium chloride
C) Calcium carbonate
D) Calcium hydroxide
✅ Correct Answer: A
Explanation: Bleaching powder is CaOCl₂, used for disinfection.
Q: The law of conservation of mass states that:
A) Mass is constant
B) Mass changes in reaction
C) Mass disappears
D) Mass can be created
✅ Correct Answer: A
Explanation: Total mass remains unchanged in chemical reactions.
Q: Which compound contains both ionic and covalent bonds?
A) CO₂
B) H₂O
C) NaCl
D) NH₄Cl
✅ Correct Answer: D
Explanation: NH₄Cl has a covalent ammonium ion and ionic bond with chloride.
Q: An alloy is a mixture of:
A) Metals
B) Elements
C) Non-metals
D) Compounds
✅ Correct Answer: A
Explanation: Alloys are metallic mixtures, like bronze or steel.
Q: The reaction of acid and base produces:
A) Salt and water
B) Salt
C) Water
D) Base only
✅ Correct Answer: A
Explanation: Acid-base reactions yield a salt and water.
Q: Solubility of solids increases with:
A) Stirring
B) Increasing temperature
C) Decreasing temperature
D) No change
✅ Correct Answer: B
Explanation: Most solids dissolve better in warmer solvents.