All Free Chemistry MCQs with Answers

• A. Because it is transition element
• B. Because it shows different oxidation states
• C. Because of extra stability of half filled d5 system
• D. Because it is typical transition element

Explanation: The correct answer is: Because of the extra stability of the half-filled d5 system.

• A. 2
• B. 3
• C. 5
• D. 7

Explanation: They can lose 1 electron from the valence d-orbital and 2 from the s-orbital.

• A. Cr
• B. Fe
• C. V
• D. Zn

Explanation: Zinc has a complete subshell. The electronic configuration of zinc is[ Ar] 3d¹⁰ 4s² so all the orbitals are filled.

• A. Rare earth elements
• B. Outer transition elements
• C. Non-typical elements
• D. Typical transition elements

Explanation: Lanthanides and actinides because of their geometrical properties are typically dispersed on earths surface and that is why they are…

• A. 2
• B. 4
• C. 6
• D. 7

Explanation: The coordination number of Pt in [PtCl(NO2)(NH3)4] is 6 because this compound has six ligands attached to the central Pt atom: one…

• A. Electric field
• B. Paired valence electrons
• C. Magnetic moment
• D. None of these

Explanation: This option is correct because the magnetic moment is the magnetic strength and orientation of a magnet object that produces a magnetic…

• A. 2B
• B. 3B
• C. 1B
• D. Both A and B

Explanation: Non-typical transition elements belong to groups 2B and 3B.Group 2B consists of the zinc group elements, which include zinc (Zn), cadmium…

• A. 3 sets
• B. 4 sets
• C. 5 sets
• D. 2 sets

Explanation: When d-orbitals are involved in bonding, they split into two sets of energy levels, one set has higher energy than the other.

• A. Coordinate covalent
• B. Ionic
• C. Metallic
• D. Covalent

Explanation: A coordination complex is the product of a Lewis acid-base reaction in which neutral molecules or anions (called ligands) bond to a…

• A. All
• B. +3
• C. +2
• D. +4

Explanation: Elements with d orbitals usually exhibit oxidation states ranging from +2 to +7.

• A. +7, +6, +2, +4
• B. +6, +7, +2, +4
• C. +7, +6, +4, +2
• D. +4, +6, +7, +2

Explanation: In KMnO4, we know that oxygen has a -2 oxidation state, and potassium has a +1 oxidation state.

• A. Sc and Zn
• B. Cu and Sc
• C. Zn and Cu
• D. Cu and Cr

Explanation: Both Cu and Cr show abnormal electronic configurations.Cu (Copper) has the electronic configuration of [Ar] 3d10 4s1 instead of [Ar] 3d9…

• A. Chelates are usually more stable than ordinary complexes
• B. Ordinary complexes are more stable than chelates
• C. Monodentate ligands form the chelates complexes
• D. Chelates have no ring structures

Explanation: Chelate ligands can form a ring with central metal. Therefore it can regulate electrons within a ring.

• A. A
• B. B
• C. C
• D. D

Explanation: The electronic configuration Mn is [Ar] 3d5 4s2. Option A is the only option that depicts this electronic configuration.

• A. Cast Iron > Wrought Iron > Steel
• B. Wrought Iron > Steel > Cast Iron
• C. Cast Iron > Steel > Wrought Iron
• D. Cast Iron < Steel > Wrought Iron

Explanation: Wrought iron is an iron alloy with a very low carbon content (less than 0.08%). Typically there is less than 0.40% carbon in most steels.

• A. +2
• B. +3
• C. -6
• D. -3

Explanation: K has a +1 charge, so K3 is +3. CN has a -1 charge, so (CN)6 is -6. So, +3 + -6 + x = 0 -3 + x = 0 x = +3 So, the oxidation state of 'Fe'…

• A. Color of ions of these metals
• B. Variable oxidation states of metals
• C. Stability associated with this configuration
• D. Complex formation tendency of metals

Explanation: Two types of electronic configurations are the most stable 1-Completely filled 2: Completely and Partially filled Example: for P subshell…

• A. Copper
• B. Cobalt
• C. Zinc
• D. Ni

Explanation: For remembering 3D series, we have a mnemonic

• A. Zinc
• B. Chromium
• C. Vanadium
• D. Manganese

Explanation: Common oxidation states of manganese are +2, +3, +4, +6, and +7, although all oxidation states from −3 to +7 have been observed.

• A. 4
• B. 7
• C. 6
• D. 5

Explanation: In the given complex six cyanide ligands are bonded to the central atom, iron.