Solutions of Carbon And Its Compounds (Page No - 240) - Chemistry Lakhmir Singh, Class 10 | Extra Documents, Videos & Tests for Class 10 PDF Download

Question 10:
Write the name and chemical formula of the simplest organic acid.
 Solution :
Formic acid; HCOOH

Question 11:
Write the IUPAC names, common names and formulae of the first two members of the homologous series of carboxylic acids.
Solution :

Question 12:
What is the common name of : (a) methanoic acid, and (b) ethanoic acid ?
 Solution :
(a) Methanoicacid – Formic acid
(b) Ethanoic acid – Acetic acid

Question 13:
Draw the structures for the following compounds :
 (a) Ethanoic acid (b) Propanoic acid
 Solution :

Question 14:
Give the common names and IUPAC names of the following compounds :
 (a) HCOOH (b) CH₃COOH
Solution :

Question 15:
Give the name and structural formula of one homologue of HCOOH.
 Solution :
Ethanoic acid; CH₃COOH

Question 16:
Write the formulae of: (a) methanoic acid, and (b) ethanoic acid.
 Solution :
(a) Methanoic acid: HCOOH
(b) Ethanoic acid: CH₃COOH

Question 17:
Give the common name and IUPAC name of C₂H₅
 Solution :
Common name: Ethyl alcohol
IUPAC name: Ethanol

Question 18:
Give the IUPAC name of the following compound :
 C₃H₇OPI
Solution :
Propanol, C₃H₇OH

Question 19:
Give the name and structural formula of one member of the following :
 Alcohols
 Solution :
Ethanol; C₂H₅OH

Question 20:
Give IUPAC names of the following compounds :
 (a) C₄H₉OH (b) C₅H_nOH
 Solution :
(a) Butanol, C₄H₉OH
(b) Pentanol, C₅H₁₁OH

Question 21:
What is the common name of methanol ?
 Solution :
Methyl alcohol

Question 22:
What is the difference between two consecutive homologues :
 (i) in terms of molecular mass ?
 (ii) in terms of number and kind of atoms per molecule ?
 Solution :
(i) 14 u
(ii) Two consecutive homologues differ by 1 carbon atom and 2 hydrogen atoms in their molecular formulae.

Question 23:
What type of fuels :
 (a) burn with a flame ?
 (b) burn without a flame ?
 Solution :
(a) Fuels which vaporise on heating, burn with a flame.
(b) Fuels which do not vaporise on heating, burn without a flame.

Question 24:
State whether the following statement is true or false :
 The minimum number of carbon atoms in a ketone molecule is two.
 Solution :
False

Question 25:
Fill in the following blanks with suitable words :
 (a) The next higher homologue of ethanol is……….
 (b) The next homologue of C₂H₅OH is……….
 (c) The next higher homologue of ethane is………..
 (d) The functional group present in ethanol is……….

Solution :
(a) Propanol
(b) C₃H₇OH
(c) Propane
(d) -OH (alcohol)
(e) Carboxylic acids

Question 26:
(a) Give the general name of the class of compounds having the general formula C_nH_2n-2.Write name of the first member of this homologous series.
 (b) The general formula of a homologous series of carbon compounds is C_nH_2n. Write the molecular formulae of the second and fourth members of the series.
 (c) Write the molecular formulae of the third and fifth members of homologous series of carbon compounds represented by the general formula C_nH_2n+2.
 Solution :
(a) Alkynes, C_nH_2n-2
First member: Ethyne
(b) Second member: C₃H₆
Fourth member: C₅H₁₀
(c) Third member: C₃H₈
Fifth member: C₅H₁₂

Question 27:
(a) Give the names and structural formulae of the next two higher homologues of methane.
 (b) The molecular formula of a hydrocarbon is C₁₀H₁₈. Name its homologous series.
 (c) Select the hydrocarbons which are members of the same homologous series. Give the name of each series.
 C₅H₁₀ ; C₃H₈; C₆H₁₀; C₄H₁₀; C₇H₁₂; C₈H₁₆
 Solution :

Question 28:
(a) Give the molecular formula of one homologue of each of the following :
 (i) C₃H₆ (ii) C₂H₆ (iii) C₂H₂
 (b) What is the difference in the molecular mass of any two adjacent homologues ?
 (c) By how many carbon atoms and hydrogen atoms do any two adjacent homologues differ ?
 Solution :
(a) (i) C₄H₈ (ii) C₃H₈
(iii) C₃H₄
(b) 14 u
(c) 1 carbon atom and 2 hydrogen atoms i.e. a CH₂ group.