All Free Chemistry MCQs with Answers
Every Chemistry question in the bank, across all chapters, each with the correct answer and a written explanation. Free and unlimited, with no account needed.
13,720 questions · page 639 of 686
- A. A
- B. B
- C. C
- D. D
Explanation: An amino acid has both a basic amine group and an acidic carboxylic acid group.
Correct answer: B- A. Disulphide bridges
- B. Weak Van Der Waal's forces
- C. Presence of unpaired electron in the structure.
- D. Hydrogen bonding between NH group of one peptide and CO group of another peptide.
Explanation: Residue in the given structure of alpha helix is due to the hydrogen bonding between the NH group of one peptide and carbonyl (C=O) of…
Correct answer: Hydrogen bonding between NH group of one peptide and CO group of another peptide.- A. Obligative.
- B. Fractional.
- C. Colligative
- D. Automated.
Explanation: Osmotic pressure is a 'colligative' property, like freezing point depression, which means that it depends on the number of particles in…
Correct answer: Colligative- A. 1
- B. 2
- C. 3
- D. 4
Explanation: Pure water (with the highest vapor pressure) will boil at the lowest temperature.Boiling occurs when vapor pressure = external…
Correct answer: 1- A. Removing K+ ions from the solution
- B. Removing ClO3- ions from the solution
- C. Adding KCl from outside
- D. Adding NaNO3 from outside
Explanation: Explanation:Adding KCl would increase the K+ ion concentration thus shifting the equilibrium to the left due to common ion effect, thus…
Correct answer: Adding KCl from outside- A. 36.5 g/mol
- B. 38.0 g/mol
- C. 100 g/mol
- D. 11.73 g/mol
Explanation: Explanation:Ar of H is 1 and Ar of Cl is 35.5. Mr = 35.5 + 1 = 36.5 g/mol
Correct answer: 36.5 g/mol- A. 5.65
- B. 7.69
- C. 5.20
- D. 4.11
Explanation: A is correct since the solution is given asGiven: Water = 103 g(1 kg), Oxygen = 5.65 x 10-3 gRequired : Oxygen in ppm = ?Formula : Ppm =…
Correct answer: 5.65- A. 314 pm
- B. 181 pm
- C. 95 pm
- D. 300 pm
Explanation: A is correct since the interionic distance of crystal lattice of KCl is 314pmB is incorrect because the interionic distance of crystal…
Correct answer: 314 pm- A. Cell
- B. Unit Cell
- C. Crystal lattice
- D. Crystal unit
Explanation: A unit cell is the smallest repeating unit of a crystal lattice that contains all the information about the crystal's structure.
Correct answer: Unit Cell12770. Al2O3(SiO2).2H2) is called:
- A. Clay
- B. Talc
- C. Asbestos
- D. None of these
Explanation: Clays used in ceramics and pottery are composed of one or more minerals and may contain up to 40-50% silica.
Correct answer: Clay- A. Co.Al2O3.3CaSO4.6H2O
- B. 3Ca.Al2O3.CaSO4.2H2O
- C. 3Ca.Al2O3.3CaSO4.2H2O
- D. 3Ca.Al2O3.3CaSO4.6H2O
Explanation: A is incorrect as the given formula isn't calcium sulpho-aluminate.B is incorrect as the given formula isn't calcium sulpho-aluminate.C is…
Correct answer: 3Ca.Al2O3.3CaSO4.2H2O- A. Isomorphism
- B. Cleavage plane
- C. Anisotropy
- D. Symmetry
Explanation: Anisotropy means having a physical property that has a different value when measured in different directions Graphite is a crystalline…
Correct answer: Anisotropy- A. Covalent solids
- B. Ionic solids
- C. Metallic solids
- D. Molecular solids
Explanation: Covalent solids is called as atomic solid because covalent solids are composed of atoms held together by covalent bonds.
Correct answer: Covalent solids- A. Electrical conductance
- B. Thermal conductance
- C. Molar mass
- D. Refractive index
Explanation: The property that does not change with the change in the direction of crystalline structure in anisotropic crystals is C, molar mass.
Correct answer: Molar mass- A. Cleavage planes
- B. Refractory planes
- C. Sagittal planes
- D. Coronal planes
Explanation: In the context of crystalline solids, cleavage planes refer to specific planes along which a crystal can break or split easily.
Correct answer: Cleavage planes- A. Rhombic
- B. Hexagonal
- C. Tetragonal
- D. Trigonal
Explanation: Graphite is hexagonal because its carbon atoms form hexagonal rings in flat layers, with each atom sp² hybridized and bonded to three…
Correct answer: Hexagonal12777. _ has dipole moment.
- A. CO
- B. CO2
- C. Benzene
- D. All of these
Explanation: In the free carbon monoxide molecule, a net negative charge δ- remains at the carbon end and the molecule has a small dipole moment of…
Correct answer: CO12778. If the electronegativity difference between bonded atoms is zero, the bond between the two atoms is:
- A. Polar
- B. Partially Ionic
- C. Non-polar
- D. Both B and C
Explanation: Explanation:If the electronegativity difference between bonded atoms is zero, the bond between the two atoms is non-polar.This option is…
Correct answer: Non-polar- A. NH3
- B. CHCl3
- C. BF3
- D. H2O
Explanation: A is incorrect because NH3 molecule has dipole moment 1.49B is incorrect because CHCl3 molecule has dipole moment 1.01C is correct since…
Correct answer: BF312780. In atomic particles:
- A. Mass of neutron is almost equal to mass of electron
- B. e/m of a proton is almost equal to e/m of electron
- C. Mass of proton is almost equal to mass of electron
- D. Charge of proton is almost equal to charge of electron
Explanation: Explanation:Both protons and electrons have the same charge in the atomic particles. Hence, the correct answer is D.
Correct answer: Charge of proton is almost equal to charge of electron