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 649 of 686
- A. A
- B. B
- C. C
- D. D
Explanation: Iodoform test is a test for the presence of a methyl ketone or a compound containing methyl group is adjacent to the functional group.
Correct answer: A- A. 1
- B. 2
- C. 3
- D. 4
Explanation: Alpha carbon is a carbon atom bonded to a functional group in an organic compound.Carbon 2 is considered to be alpha because it has a…
Correct answer: 2- A. 2, 4-Dinitrophenyl hydrazine
- B. 1, 3-Dinitrophenyl hydrazone
- C. Phenyl hydrazone
- D. 2, 4-Dinitrophenyl hydrazone
Explanation: Hydrazone consists of a carbon-nitrogen double bond, i.e., R1R2C=NNH2. In Phenyl hydrazone, one H atom of hydrazone is replaced by a…
Correct answer: 2, 4-Dinitrophenyl hydrazine12964. Which one of the following compounds will give iodoform test on treatment with aqueous iodine?
- A. 3-pentanone
- B. Propanone
- C. Propanal
- D. Butanal
Explanation: Compounds that give a positive iodoform test are primary alcohol, methyl alcohol and methyl ketones.
Correct answer: Propanone- A. Option A
- B. Option B
- C. Option C
- D. Option D
Explanation: Ketones react with HCN in nucleophilic addition reaction and the product is a cyanohydrin i.e a compound which has OH and CN both bonded…
Correct answer: Option A- A. Carbolic Acid
- B. Acetic Acid
- C. Carbonic Acid
- D. Oxalic Acid
Explanation: Explanation:Acetic acid is used in the manufacture of plastics such as poly vinyl acetate (rayon) and cellulose acetate (silk).Carbolic…
Correct answer: Acetic Acid- A. H3C-COO-C2H5
- B. H3C2-COO-CH3
- C. H3C2-CO-OH
- D. H3C2-COO-C2H5
Explanation: A is incorrect as the compound given is an ester which does not produce carbon dioxide upon reaction with sodium carbonate.B is incorrect…
Correct answer: H3C2-CO-OH- A. CCl3COOH > CHCl2COOH > CH2ClCOOH > CH3COOH
- B. CH3COOH > CHCl2COOH > CCl3COOH > CH2ClCOOH
- C. CHCl2COOH > CH3COOH > CCl3COOH > CH2ClCOOH
- D. CCl3COOH > CH3COOH > CHCl2COOH > CH2ClCOOH
Explanation: CCl3COOH > CHCl2COOH > CH2ClCOOH > CH3COOH: This option suggests that trichloroacetic acid (CCl3COOH) is the strongest acid, followed by…
Correct answer: CCl3COOH > CHCl2COOH > CH2ClCOOH > CH3COOH- A. Diethyl ether
- B. Methyl propyl ether
- C. Ethyl acetate
- D. Butyl alcohol
Explanation: Ethyl Acetate is an ester that is made when Ethanoic acid reacts with Ethanol.
Correct answer: Ethyl acetate- A. CH3COOH > ClCH2COOH > Cl2CHCOOH > Cl3CCOOH
- B. CH3COOH > Cl2CHCOOH > Cl3CCOOH > ClCH2COOH
- C. Cl3CCOOH > Cl2CHCOOH > ClCH2COOH > CH3COOH
- D. Cl3CCOOH > CH3COOH > Cl2CHCOOH > ClCH2COOH
Explanation: Chlorine is an electronegative atom and it pulls the electron density towards itself thus spreading the charge and making the conjugate…
Correct answer: Cl3CCOOH > Cl2CHCOOH > ClCH2COOH > CH3COOH- A. Solid.
- B. Liquid.
- C. Gas
- D. Isotope
Explanation: In thermodynamics, in the PV diagram, if liquid and vapor are present in equilibrium at a point, we call it a critical point.
Correct answer: Liquid.12972. At a given temperature and pressure, the one which shows marked deviation from ideal behavior is
- A. N2
- B. N3
- C. CO2
- D. He
Explanation: The gas with higher intermolecular forces has the most marked deviation, as one of the assumptions of an ideal gas is that ideal gases…
Correct answer: CO2- A. Strong
- B. Moderate
- C. Weak
- D. Absent
Explanation: In an ideal gas, it is assumed that the intermolecular forces between gas molecules are absent.
Correct answer: Absent- A. Low temperature and low pressure
- B. High temperature and high pressure
- C. Low temperature and high pressure
- D. High temperature and low pressure
Explanation: Deviation from ideal gas behavior occurs primarily under high pressure and low temperature conditions.
Correct answer: Low temperature and high pressure- A. Copper metal
- B. Copper ions
- C. Hydrogen
- D. Oxygen
Explanation: Since reduction takes place cupric ions present in the electrolyte gain two electrons and get converted into copper metal.
Correct answer: Copper metal- A. Cd
- B. Ni(OH)2
- C. Ni
- D. NiO2
Explanation: Explanation:The correct option is NiO2 because the cathode in a nickel-cadmium battery is typically composed of nickel oxyhydroxide…
Correct answer: NiO2- A. Tin plating
- B. Zinc plating
- C. Nickel plating
- D. Copper plating
Explanation: Explanation:The most durable metal plating on iron to protect against corrosion is zinc plating.
Correct answer: Zinc plating- A. Hydrolysis reaction
- B. Oxidation reaction
- C. Redox reaction
- D. Reduction reaction
Explanation: The correct answer is C: Redox reaction. In a voltaic cell, the production of electricity is due to redox reactions, where oxidation and…
Correct answer: Redox reaction- A. Zn+2 + Cu → Cu+2 + Zn
- B. Zn + MgSO4 → ZnSO4 + Mg
- C. Fe + CuSO4 → FeSO4 + Cu
- D. Cd + MgSO4 → CdSO4 + Mg
Explanation: Fe + CuSO₄ → FeSO₄ + Cu is feasible because iron has a lower reduction potential (-0.44 V) than copper (+0.34 V), meaning iron is more…
Correct answer: Fe + CuSO4 → FeSO4 + Cu- A. Option A
- B. Option B
- C. Option C
- D. Option D
Explanation: Explanation:It is the fact. Equilibrium constant is products/reactants.
Correct answer: Option C