Free Functional Groups MCQs with Answers
49 Functional Groups MCQs from Chemistry, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
Functional groups are specific atoms or atom groups that determine the characteristic reactions and properties of organic compounds. Coverage includes alkenes, alkynes, halo, hydroxyl, ether, carbonyl, carboxyl, ester, amino and nitro groups, together with their structures, nomenclature and related homologous series.
Last updated
49 questions · page 1 of 3
- A. a hydroxyl group
- B. a carbonyl group at the end of the chain, written CHO
- C. a carboxyl group
- D. a carbonyl group between two carbon atoms
Explanation: In an aldehyde the carbonyl carbon carries at least one hydrogen and so must be terminal, whereas in a ketone the same carbonyl group lies…
Correct answer: a carbonyl group at the end of the chain, written CHO- A. an alkane
- B. an alkyne
- C. an alcohol
- D. an alkene or a cycloalkane
Explanation: Both an alkene, with one double bond, and a cycloalkane, with one ring, have two hydrogens fewer than the corresponding alkane, so they…
Correct answer: an alkene or a cycloalkane- A. COOH
- B. CHO
- C. OH
- D. CO
Explanation: The carboxyl group combines a carbonyl and a hydroxyl on the same carbon atom, and this arrangement makes the hydrogen far more acidic…
Correct answer: COOH- A. COOR, formed by replacing the acidic hydrogen of a carboxylic acid
- B. OH attached to a benzene ring
- C. NH2 attached to a carbon chain
- D. a carbon to carbon triple bond
Explanation: An ester is formed when a carboxylic acid reacts with an alcohol, water being eliminated, and the resulting group is responsible for the…
Correct answer: COOR, formed by replacing the acidic hydrogen of a carboxylic acid- A. Methane
- B. Ethanol
- C. Acetic acid
- D. Urea
Explanation: Heating ammonium cyanate causes rearrangement into urea, NH2CONH2, an organic compound containing a carbonyl group bonded to two amino…
Correct answer: Urea- A. Sodium hexadecanoate
- B. Sodium octadecanoate
- C. Sodium pentadecanoate
- D. Both A & B
Explanation: Sodium hexadecanoate and sodium octadecanoate are soaps whose anions form insoluble calcium and magnesium salts, producing curdy scum in…
Correct answer: Both A & B- A. Bromine
- B. Fluorine
- C. Chlorine
- D. Sulphur
Explanation: Ethyl mercaptan, CH3CH2SH, contains a thiol group with sulfur, so sulfur gives the compound its characteristic odour.
Correct answer: Sulphur- A. Methanamide
- B. Methanoylamine
- C. Aminoethanol
- D. Formanide
Explanation: HCONH2 is the amide derived from methanoic acid by replacing the acid hydroxyl group with NH2.
Correct answer: Methanamide- A. Nitrogen gas
- B. NH3
- C. CN‾
- D. NO
Explanation: In Lassaigne's sodium-fusion test, nitrogen in an organic compound is converted into sodium cyanide, NaCN.
Correct answer: CN‾- A. Cl
- B. N2
- C. CO2
- D. CO
Explanation: The Beilstein test detects halogens in an organic compound by producing a volatile copper halide that gives a coloured flame.
Correct answer: Cl- A. ethylene glycol
- B. glycerol
- C. picric acid
- D. ethyl acetate
Explanation: Ethyl acetate, CH3COOCH2CH3, is an ester and contains no hydroxyl, or -OH, group.
Correct answer: ethyl acetate- A. CH3NH2
- B. CH3NO2
- C. CH3CN
- D. CH2 = CH - CN
Explanation: Methyl cyanide is acetonitrile, whose condensed formula is CH3CN; the -CN group is the nitrile functional group.
Correct answer: CH3CN- A. CH2Cl2
- B. CH3Cl
- C. CHCl3
- D. CCl4
Explanation: Chloroform is trichloromethane, so three hydrogen atoms of methane are replaced by chlorine and its formula is CHCl3.
Correct answer: CHCl3- A. Grignard reagent
- B. Metallic alkyl halide
- C. Both A & B
- D. Alkyl
Explanation: R-Mg-Br is an organomagnesium halide called a Grignard reagent, and it contains an alkyl group directly bonded to a metal, so it is also…
Correct answer: Both A & B- A. Imino group
- B. Amino group
- C. Amide group
- D. Nitro group
Explanation: Aniline is aminobenzene, with an -NH2 group directly attached to the benzene ring, so it contains an amino group.
Correct answer: Amino group- A. Hydrogen
- B. Oxygen
- C. Sulphur
- D. OH
Explanation: Benzene sulphonic acid has the structure C6H5SO3H, so the benzene carbon is directly bonded to the sulphur atom of the sulphonic group.
Correct answer: Sulphur- A. radical
- B. hydrocarbon
- C. functional group
- D. ion
Explanation: A functional group is a specific atom or group of atoms that gives an organic compound its characteristic chemical reactions and…
Correct answer: functional group- A. OH
- B. R-CO-R
- C. R-O-R
- D. R-COOH
Explanation: An ether contains an oxygen atom single-bonded to two carbon-containing groups, represented generally as R-O-R.
Correct answer: R-O-R- A. R-NH2
- B. RCONH2
- C. R - NH - R
- D. C6H5NH2
Explanation: An amide contains a carbonyl group directly attached to nitrogen, represented by RCONH2.
Correct answer: RCONH2- A. They are usually volatile liquids
- B. Show weak hydrogen bonding
- C. They are highly flammable with low boiling points
- D. It is poisonous and is used as a disinfectant in hospitals
Explanation: Ethers are generally volatile liquids with low boiling points because they cannot form strong intermolecular hydrogen bonds.
Correct answer: It is poisonous and is used as a disinfectant in hospitalsFunctional Groups MCQs: common questions
Are these Functional Groups MCQs free?
Yes. All Functional Groups MCQs from Chemistry are free on TestUstad, with unlimited attempts and no account needed. Nothing on this page is a sample or a trial.
How many Functional Groups MCQs are on this page?
There are 49 Functional Groups MCQs in the Chemistry bank, shown 20 to a page with the correct answer and an explanation on each.
Does every Functional Groups MCQ have an explanation?
Yes. Each Functional Groups question shows the correct option and a written explanation of why it is correct, so a wrong answer teaches you something rather than just being marked wrong.
Can I take a timed Functional Groups test?
Yes. The practice button on this page starts a free Functional Groups test drawn from the Chemistry bank. It marks each answer instantly, gives you a score at the end, and can be retaken as many times as you like.