All Free Chemistry MCQs with Answers

• A. Tetrahedral
• B. Trigonal bipyramidal
• C. Octahedral
• D. Square planar

Explanation: For molecules and polyatomic ions, the coordination number of an atom is determined by simply counting the other atoms to which it is…

• A. I
• B. Fe
• C. Ca
• D. Mg

Explanation: Out of the given options, Fe is the only transition element. Ca and Mg are alkaline earth metals whereas Iodine (I) is a halogen.

• A. Red-Blue
• B. Blue
• C. Colorless
• D. Green

Explanation: The ion Sc+3 is colorless, Sc+3 is a 3d0 system. There are no d electrons; hence, d-d transition is not possible.

• A. Intervening electrons
• B. d-shell
• C. Screening effect
• D. Shielding effect

Explanation: Due to the poor shielding effect of d-electrons, the outer electrons experience a more effective nuclear charge.

• A. 3A
• B. 3B
• C. 2B
• D. 1B

Explanation: Copper, silver and gold are coinage metals. They belong to group 1B of the periodic table.

• A. Triangular
• B. Trigonal pyramidal
• C. Tetrahedral
• D. Octahedral

Explanation: Transition metal complexes with a coordination number of 6 show octahedral geometry.

• A. [Co(H₂O)]²⁺
• B. [Co(H₂O)₆]-
• C. [CO(H₂O)₆]
• D. [Co(H₂O)₆]²⁺

Explanation: From the written formula, (II) indicates the complex has a +2 charge. Hexa-aquacobalt means there are 6 water molecules attached to one…

• A. Increases
• B. Increases and then decreases
• C. Rapidly decreases and then becomes constant
• D. Decreases and then increases

Explanation: Over all trend can be explained based two factors that are working there, nuclear attractions and inter electronic repulsions, where one…

• A. Blue and red
• B. Green
• C. Yellow
• D. Violet

Explanation: In [Ti(H₂O)₆]³⁺, the Ti atom has one valence electron which is excited when it absorbs yellow light.

• A. Sc, Y, La
• B. Sc, Cu, Au
• C. Cu, Ag, Au
• D. Zn, Cd, Hg

Explanation: Group III B has the following elements: Scandium (Sc) Yttrium (Y) Lanthanum (La) Actinium (Ac) Zn, Cd, Hg are members of group II B while…

• A. Black
• B. Orange
• C. White
• D. Green

Explanation: Copper, a reddish-brown solid, when heated in air is oxidized to Copper (II) oxide or cupric oxide. It is a black solid.

• A. Cr, Ag, Al
• B. Ag, Mn, Ni
• C. Cr, Mn, Ni
• D. Cu, Au, Mn

Explanation: Alloy steel is made up of many elements such as iron, carbon, vanadium, silicon, nickel, manganese, copper and chromium.

• A. Hg
• B. Zn
• C. C
• D. Fe

Explanation: Iron (Fe) is the most stable element in the periodic table as its structure, particularly its nucleus, is the most stable out of all the…

• A. Due to both s and d orbitals
• B. Due to s orbitals
• C. Due to d orbitals
• D. Due to unpaired electrons

Explanation: Transition elements have incomplete d orbitals, which allow electrons in other orbitals like s orbitals to get excited and jump into these…

• A. Ionic
• B. Coordinate covalent
• C. None of these
• D. Covalent

Explanation: A coordinate covalent bond, also known as a dative bond, is a kind of two-center, two-electron covalent bond in which the two electrons…

• A. Quantum Leap
• B. Orbital delocalization
• C. d-d splitting
• D. d-d splitting and orbital delocalization

Explanation: When the ligands approach the central metal ion, d- or f-subshell degeneracy is broken due to the static electric field.

• A. All of these
• B. Nickel
• C. Cobalt
• D. Iron

Explanation: Iron, cobalt, and nickel are important transition elements that are used in industries and are part of various machinery and appliances as…

• A. Complex ion
• B. Ligand
• C. Coordination sphere
• D. Complex compound

Explanation: The correct option for the given question is C) Coordination sphere. The coordination sphere refers to the central transition metal ion…

• A. Increases
• B. Decreases
• C. Remain the same
• D. No regular trend

Explanation: The melting points and boiling points of the 3d transition metals increase up to the middle of the series and then decrease.This is…

• A. +7
• B. -7
• C. +6
• D. -6

Explanation: Oxidation no of Mn=?Oxidation no of O=-2Overall charge on coordination sphere=-2Mn+4(-2)=-2Mn-8=-2 Mn=8-2Mn=+6