Chemistry

Practice the latest Chemistry MCQs with answers and explanations to prepare for exams and job tests. Our collection covers key topics such as atomic structure, periodic table, chemical bonding, organic chemistry, inorganic chemistry, physical chemistry, and environmental chemistry. These Chemistry multiple-choice questions are designed for students, competitive exam aspirants, and professionals appearing in NTS, PPSC, FPSC, CSS, PMS, university entry tests, and medical admission tests. Improve your concepts and problem-solving skills with our updated and comprehensive Chemistry MCQs online.

121. Soda lime is a mixture of

September 17, 2025 by Admin

A. CaO and KOH

B. CaO and NaOH

C. NaOH and Na2O

D. Na2O and KOH

✅ The correct answer is option B.

123. Unit of the rate of reaction is

September 17, 2025 by Admin

A. Moles dm-3 sec-1

B. Moles dm-3

C. Moles sec-1

D. Mol-1 dm3 sec-1

✅ The correct answer is option A.

124. Molozonide is unstable and changes into ozonide on

September 17, 2025 by Admin

A. Reduction

B. Oxidation

C. Hydrolysis

D. Rearrangement

✅ The correct answer is option D.

126. Dehalogenation of ethyl tetrahalide will give

September 17, 2025 by Admin

A. Ethene

B. Ethyne

C. Ethyl halide

D. All of the above are possible

✅ The correct answer is option B.

128. All of the following were theorized by Bohr in his description of the atom except

September 17, 2025 by Admin

A. The angular momentum of electrons in multiples of h/2?

B. Electrons revolve in discrete circular orbits

C. The energy of each electron is directly proportional to n2

D. Electrons radiate energy continuously in a given orbit

✅ The correct answer is option D.

130. The letters sp d and f are used to represent which quantum numbers

September 17, 2025 by Admin

A. Principal

B. Azimuthal

C. Magnetic

D. Spin

✅ The correct answer is option B.