All Free Chemistry MCQs with Answers

• A. Zn
• B. Hg
• C. Cu
• D. Fe

Explanation: Zinc: Zinc is the main metal in brass, but it is not present in bronze.Mercury: Mercury is a liquid metal that is not used in the…

• A. Au
• B. Ag
• C. Cu
• D. AlI of these options are correct

Explanation: All these three Au(gold), Ag(silver) and Cu (copper) are coinage metals and are used in making of coins.

• A. Fe2+
• B. Mn2+
• C. Cr5+
• D. Zn2+

Explanation: Option A: In Fe[2],The electrons fill up 3d orbitals after 4s orbitals are filled.

• A. 3
• B. 4
• C. 6
• D. 1

Explanation: The coordination number of an atom in a given molecule or a crystal refers to the total number of atoms, ion, or molecules bonded to the…

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

Explanation: The sp3d2 hybridization leads to a central metal that has an octahedral geometry.

• A. Complex formation
• B. Color
• C. Fixed valency
• D. D-orbital

Explanation: The transition metal ions have unpaired d electrons which jump from one orbital to another.

• A. Anion
• B. Cation
• C. Ligand
• D. Acid

Explanation: A ligand is a specie that donates electrons to the central metal ion forming a dative covalent bond.

• A. Ligand field theory
• B. Crystal field theory
• C. Molecular orbital theory
• D. Both A and B

Explanation: Option C : In molecular orbital theory, electrons in a molecule are not assigned to individual chemical bonds between atoms but are…

• A. Because of high melting point
• B. Because d-electrons of the outer shell take part in bonding
• C. Because s-electrons of the outer shell take part in bonding
• D. Both s and d electrons take part in bonding

Explanation: Metallic bonding is a type of chemical bonding that arises from electrostatic attractive forces between conduction electrons in the form…

• A. Activation
• B. Enamelling
• C. Corrosion
• D. Coating

Explanation: Option A : The process where something is prepared or excited for a subsequent reaction.

• A. Potassium tetra cyano recuperate
• B. Coordination number is 2
• C. The ligand is positively charged
• D. Central atom is present in the anionic sphere

Explanation: The following compound is an atom with the lowest subscript in the molecular formula and the atom that can form the most bonds in a…

• A. Na
• B. Co
• C. Ba
• D. Ra

Explanation: Transition elements (transition metals) have partially filled d orbitals.

• A. 0
• B. 8
• C. 6
• D. 4

Explanation: Let 'x' be the oxidation number of 'Ni' in Ni(CO)4.Since the overall charge of the complex is 0, the sum of the oxidation states of all…

• A. Zn
• B. Mg
• C. H
• D. All of these

Explanation: Hydrogen is the only element that is small enough to fit into the interstices of transition metals.

• A. Orbitals of f-subshell
• B. Orbitals of d-subshell
• C. Orbitals of p-subshell
• D. Both Options A and B are correct

Explanation: Transition elements are d and f block elements, i.e. their valence shell configuration ends at the d or f block.

• A. CaSiO3
• B. Na2SiO3
• C. Ca3(PO4)2
• D. MnSiO3

Explanation: Option A) CaSiO3, also known as calcium silicate, is not typically used as a fertilizer, but it is used in construction materials and…

• A. 2
• B. 1
• C. 3
• D. 0

Explanation: Reason: Scandium has multiple oxidation states but the most common one is +3.

• A. Transition elements
• B. Typical transition elements
• C. Outer transition elements
• D. Inner transition elements

Explanation: The elements in which d or f orbitals are in completion are called d and f block elements collectively called transition elements.

• A. Increases from left to right
• B. Decreases from left to right
• C. Increases up to middle then decreases
• D. Decreases up to middle than increases

Explanation: Melting and boiling points of transition elements along a period are directly proportional to the number of unpaired electrons.

• A. s electrons
• B. Unpaired electrons
• C. Paired electrons
• D. Outer d electrons

Explanation: Option B is correct as paramagnetism (the ability of a material to be weakly attracted to a magnet due to its magnetic field, which…