All Free Chemistry MCQs with Answers

• A. Polar
• B. Non-polar
• C. Reactive
• D. Non-reactive

Explanation: Option BHalogen are non polar , discrete diatomic in all phases( gas,liquid,solid).

• A. SF4
• B. SiF4
• C. BF3
• D. XeF4

Explanation: SF4 has sp3d hybridization so possesses a seesaw structure and has a permanent dipole moment.

• A. Charge
• B. Mass
• C. Magnitude of charge
• D. Both A and B

Explanation: The explanation for this question will be added soon.

• A. 1842
• B. 1/1836
• C. 1836
• D. 1840

Explanation: Protons are 1836 times heavier than electrons.

• A. 1838 times more than mass of proton
• B. 1836 times less than mass of proton
• C. 1836 times more than mass of neutron
• D. 1836 times more than mass of hydrogen atom

Explanation: The mass of an electron is only about 1/2000 the mass of a proton or neutron, so electrons contribute virtually nothing to the total mass…

• A. Isomers
• B. Protons
• C. Isotopes
• D. Nucleus

Explanation: Option A: Isomers are compounds that have the same molecular formula but different structural arrangements or spatial orientations.

• A. Nature of gas
• B. Properties of gas
• C. Composition of gas
• D. All of these

Explanation: The e/m value of positive particles (anode rays) depends on the gas taken in the discharge tube. This content is given in the FSC book.

• A. 1889, electrons
• B. 1886, electrons
• C. 1836, protons
• D. 1836, electrons

Explanation: Remember that the mass of a proton is 1836 times heavier than that of an electron.

• A. Oxygen gas, lowest
• B. Hydrogen gas, highest
• C. Hydrogen gas, lowest
• D. Helium gas, highest

Explanation: Correct option is C. The highest value of e/m of anode rays has been observed when the discharge tube is filled with hydrogen.

• A. Hund's Rule
• B. Pauli's exclusion principle
• C. Aufbau's principle
• D. Heisenberg's principle

Explanation: The explanation for this question will be added soon.

• A. N+1 rule
• B. Aufbau's principle
• C. Hund's rule
• D. It is not filled before 3d

Explanation: The explanation for this question will be added soon.

• A. 2
• B. 6
• C. 10
• D. 14

Explanation: Each p subshell holds at most 6 electrons.

• A. 4s
• B. 2p
• C. 2d
• D. 3s

Explanation: The orbital energies are compared with the help of n+l rule. The higher value of n+l, higher is the energy of the orbital.

• A. Aufbau Principle
• B. n+I Rule
• C. Hund's Rule
• D. Pauli's Exclusion Principle

Explanation: According to Hund's rule every orbital in a subshell is singly occupied with one electron before any one orbital is doubly occupied, and…

• A. Aufbau Principle
• B. n + l rule
• C. Hund's rule
• D. Pauli exclusion principle

Explanation: Hund's rule explains the electronic configuration of degenerate orbitals

• A. Li+2
• B. H+
• C. He+
• D. Be

Explanation: The charge to mass ratio is called the e/m ratio. e/m ratio is a physical quantity, widely used in the electrodynamics of charged…

• A. 18
• B. 10
• C. 17
• D. 8

Explanation: Option A: This option suggests that the chloride ion (Cl-) has 18 valence electrons. However, this is incorrect.

• A. 2(l+1)
• B. l+1
• C. n+l
• D. 2(n+l)

Explanation: The arrangement of subshells or orbitals within an atom is based on the principle known as the Aufbau principle.

• A. 50
• B. 49
• C. 48
• D. 44

Explanation: No. of (proton=electron)=(atomic no.)No. of neutron=Atomic no. - no. of protonIn case of H2SO4,H2 = 2 protons & 2electronS = 16…

• A. 24
• B. 5
• C. 72
• D. 98

Explanation: Calculate this by using the 2n2 formula. In the formula 2n², n = 7 so 2(7)², 2(49), "98".