1. Two adjacent members of a homologous series have : (a) a difference of –CH2 in their structure (b) a difference of 14 a.m.u. in molecular mass (c) same general methods of preparation (d) all of the above Ans: D
2. Alkenes are characterized by (a) C – C bonds (b) C = C bonds (c) C [latex]\equiv[/latex] C bonds (d) cyclic structure Ans: B
3. Which of the following contains carbonyl group? (a) Ketones (b) Aldehydes (c) Esters (d) All of these Ans: D
4. The functional group present in CH₃COOC₂H₅ is (a) ketonic (b) aldehydic (c) ester (d) carboxylic Ans: C
5. Butanone is a four-carbon compound with the functional group (a) carboxylic acid (b) aldehyde (c) ketone (d) alcohol Ans: C
6. Which of the following is incorrectly matched? (a) Vinegar [latex]\rightarrow[/latex] carboxylic acid (b) C2H6 [latex]\rightarrow[/latex] alkane (c) Ethanol [latex]\rightarrow[/latex] alcohol (d) Methanol [latex]\rightarrow[/latex] ketone Ans: D
7. If a hydrocarbon has any double bond, it is (a) alkyne (b) alkane (c) alkene (d) All the above Ans: C
8. Alkynes are characterized by – (a) C – C bonds (b) C = C bonds (c) C [latex]\equiv[/latex] C bonds (d) cyclic structure Ans: C
9. How many different isomers are possible for a hydrocarbon with the molecular formula C₄H₁₀? (a) 1 (b) 2 (c) 3 (d) 5 Ans: B
10. The general formula C_nH_2nO₂ could be for open chain (a) diketones (b) carboxylic acids (c) diols (d) dialdehydes Ans: B
11. The IUPAC name of CH₃CH₂COCl is (a) propanoyl chloride (b) ethanoyl chloride (c) acetyl chloride (d) chloroethane Ans: A
12. General formula of alkenes and alkyl radicals are respectively: (a) C_nH_2n and C_nH_2n+1 (b) C_nH_2n and C_nH_2n+2 (c) C_nH_2n-1 and C_nH_2n (d) C_nH_2n+1 and C_nH_2n+2 Ans: A
13. The IUPAC name of CH₃COOC₂H₅ will be – (a) ethyl acetate (b) ethyl ethanoate (c) methyl propanoate (d) none of these Ans: B
14. While cooking, if the bottom of the vessel is getting blackened on the outside, it means that (a) the food is not cooked completely. (b) the fuel is not burning completely. (c) the fuel is wet. (d) the fuel is burning completely Ans: B
15. Which is a general formula of alkenes? (a) C_nH_2n+2 (b) C_nH₂n (c) C_nH_2n–2 (a) None of these Ans: A
16. Organic compounds will always contain (a) carbon (b) hydrogen (c) nitrogen (d) sulphur Ans: A
17. Methane, ethane and propane are said to form a homologous series because all are (a) hydrocarbons (b) saturated compounds (c) aliphatic compounds (d) differ from each other by a CH₂ group Ans: D
18. General formula of alkyne is (a) C_nH_2n+2 (b) C_nH_2n (c) C_nH_2n–2 (d) C_nH_n Ans: C
19. Which among the following are unsaturated hydrocarbons? (a) (i) and (iii) (b) (ii) and (iii) (c) (ii) and (iv) (d) (iii) and (iv) Ans: C
20. Pentane has the molecular formula C₅H₁₂. It has (a) 5 covalent bonds (b) 12 covalent bonds (c) 16 covalent bonds (d) 17 covalent bonds Ans: C
21. The heteroatoms present in [latex]CH_{3} -- CH_{2} -- O — CH_{2} -- CH_{2}Cl[/latex] are (i) oxygen (ii) carbon (iii) hydrogen (iv) chlorine (a) (i) and (ii) (b) (ii) and (iii) (c) (iii) and (iv) (d) (i) and (iv) Ans: D
22. Isomers of a substance must have the same (a) structural formula (b) physical properties (c) chemical properties (d) molecular formula Ans: D