CBSE Class 10 Science Carbon and its compounds Assignment Set D

Very Short answer Type Questions

Question. Write the name and formula of second member of homologous series with general formula C_nH2_n+2
Answer: C₂H₆, Ethane

Question. Write the name and formula of second member of homologous series having general formula C_nH2_n–2.
Answer: C₃H₄, Propyne

Question. Draw electron dot structure of NH₃ molecule. Predict the total no. of bonds around N-atom.
                                                                              OR
A molecule of ammonia has the formula NH₃. Predict the total number of bonds present around nitrogen atom. 
Answer: 

Question. Write the next homologue of each of the following: (i) C₂H₄, (ii) C₄H₆ 
Answer: (i) C₃H₆, (ii) C₅H₈

Question. Write the structure of an alcohol with three carbon atoms in the molecule.
Answer: 

Question. Write the molecular formula of alcohol derived from butane.
Answer: C₄H₉OH or CH₃CH₂CH₂CH₂OH (Butan-1-ol)

Question. Write the molecular formula of an alkyne containing 10 atoms of hydrogen.
Answer: C₆H₁₀

Question. Write the name and molecular formula of the fourth member of alkane series. 
Answer: C₄H₁₀, Butane (CH₃CH₂CH₂CH₃)

Question. Which of the following organic compounds belong to the same homologous series:
C₂H₆, C₂H₆O, C₂H₆O₂, CH₄O
Answer: C₂H₆O (C₂H₅OH) and CH₄O (CH₃OH)

Question. The formula of citric acid is shown below:

State the name of —COOH functional group in citric acid.
Answer: Carboxylic acid

Question. Why covalent compounds are poor conductors of electricity? 
​​​​​​​Answer: It is because covalent compounds do not form ions. 

Question. What would be the electron dot structure of carbon dioxide which has the formula, CO₂?
 ​​​​​​​Answer: 

Question. Which element exhibits the property of catenation to maximum extent and why?
​​​​​​​Answer: Carbon since it forms strong covalent bond, due to smaller atomic size.

Question. Write the molecular formula of first two members of homologous series having functional group Cl.
​​​​​​​Answer: The general formula of the compounds having – Cl functional group is CnH2n + 1Cl. Its two members are:
(i) CH₃Cl (ii) CH₃ – CH₂ – Cl

Question. Write the molecular formula of the 2nd and the 3rd member of the homologous series whose first member is methane (CH₄). 
​​​​​​​Answer: (i) CH₃CH₃ (Ethane); where n is 2
(ii) CH₃CH₂CH₃ (Propane); where n is 3

Question. Write the number of covalent bonds in the molecule of butane (C₄H₁₀). 
​​​​​​​Answer: There are 13 covalent bonds.

Question. State the valency of the carbon atom in (i) an alkane (ii) an alkyne.
​​​​​​​Answer: (i) Four, (ii) Four

Question. Name a cyclic unsaturated carbon compound. 
​​​​​​​Answer: Benzene is cyclic unsaturated carbon compound.

Question. The molecular formula of ‘A’ is C₁₀H₁₈ and ‘B’ is C₁₈H₃₆. Name the homologous series to which they belong. 
​​​​​​​Answer: ‘A’ belongs to Alkynes, ‘B’ belongs to Alkenes.

Question. Write the next homologous of CH₃CH₂OH and HCOOH.
​​​​​​​Answer: CH₃ – CH₂ – CH₂OH. Propanol and, CH₃COOH ethanoic acid

Short answer Type Questions

Question. How many covalent bonds are there in a molecule of ethane, C₂H₆?
​​​​​​​Answer: There are seven covalent bonds in a molecule of ethane:

Question. Name the functional group present in each of the following organic compound:
(i) CH₃COCH₃ (ii) C₂H₅COOH
​​​​​​​Answer: (i) CH₃COCH₃ —- >C=O ketonic group (ii) C₂H₅COOH — (-COOH) Carboxylic acid

Question. Write the name and formula of the 2nd member of homologous series having general Formula CnH₂n.
​​​​​​​Answer: CnH2n: alkene Name: propene(2nd member) formula: C₃H6

Question. Select saturated hydrocarbons from the following:
C₃H₆, C₅H₁₀, C₄H₁₀, C₆H₁₄, C₂H₄
​​​​​​​Answer: Saturated hydrocarbons:
General formula= CnH₂n⁺²
C₄H₁₀, C₆H₁₄

Question. Write the electron dot structure of ethane molecule, C₂H₄​​​​​​​
Answer: 

​​​​​​​

Question. Draw the structure of ethanoic acid molecule, CH₃COOH
​​​​​​​Answer: Structure of ethanoic acid molecule:

Question. Name the functional group present in each of the following organic compounds.
(i) C₂H₅Cl (ii) C₂H₅OH
​​​​​​​Answer: Functional group present in:
(i) C₂H₅Cl – chloro(halide) (ii) C₂H₅OH —- Alcohol

Question. Write the name and structure of an alcohol with three carbon atoms in its molecule.
​​​​​​​Answer: Name of an alcohol: Propanol
Structure of propanol: H₂C – CH₂ – CH₂ – OH

Question. What are isomers? Draw the structure of two isomers of butane C4H10.
​​​​​​​Answer: The organic compounds having the same molecular formula but different structures are known as isomers. Isomers of butane C₄H₁₀.

Question. What are homologous series of carbon compounds? Write the molecular formula of two Consecutive members of homologous series of aldehydes.
​​​​​​​Answer: A series of carbon compounds in which the same functional group substitutes for Hydrogen on a carbon chain is called homologous series. There is difference of –CH₂ in nThe molecular formula of two nearest compounds of a homologous series. Each such Series has same general molecular formula and has a general scientific name. There Is a difference of 14u in the molecular mass of two nearest compound of a series?
Members of homologous series of aldehydes:
H – CHO
CH₃ – CHO
C₂H₅ – CHO

Long answer Type Questions

Question. List two reasons for carbon forming a large number of compounds. Name the type of Bonding found in most of its compounds. Why does carbon form compounds mainly by this kind of bonding?
​​​​​​​Answer: Carbon forms a large number of compounds.
The two properties of carbon which lead to the huge number of carbon compounds are:
-catenation: it’s a unique property of carbon atoms to form bonds with other atoms of Carbon giving rise to large molecules.
-Tetravalency: Since carbon has four valencies, it is capable of bonding with four other atoms Of carbon or atoms of some other monovalent elements.
Carbon compounds are formed mainly by sharing of electron with covalent bond because carbon atoms have 4 electrons in their outermost shell. So, needs to gain or lose Electrons to achieve inert gas electronic configuration. It could gain four electron forming C4-anion. But it is difficult due to energy consideration. It could lose 4 electrons to form C4+cation. But it is difficult due to energy consideration.
Because of this reason carbon Share their electron to form covalent bond only.

Question. What are covalent compounds? Why are they different from ionic compound? List any Three characteristics properties.
​​​​​​​Answer: (i) The chemical bond formed by the sharing of electrons between two atoms is known as a covalent bond. The molecules formed by sharing of electrons between two or more same atoms or between two or more non-metals are called covalent compound.
(ii)Covalent compounds are different from ionic compounds as ionic compounds are Formed by transfer of electrons.
Characteristics of covalent compound:
(i) Covalent compounds usually have low melting and boiling point because force Of attraction between molecules is very weak.
(ii) Covalent compounds are usually insoluble in water but they are soluble in organic compound.
(iii) Covalent compounds do not conduct electricity as they do not contain ions.

Case Study Questions Chapter 4 Carbon And Its Compound

Case/Passage – 1
There is a pair of bean-shaped organs P in the human body towards the back, just above the waist. A waste product Q formed by the decomposition of unused proteins in the liver is brought into organ P through blood by an artery R. The numerous tiny filters S present in organ P clean the dirty blood y removing the waste product Q. The clean blood goes into circulation through a vein T. The waste substance Q, other waste salts, and excess water form a yellowish liquid U which goes from organ P into a bag-like structure V through two tubes W. This liquid is then thrown out of the body through a tube X.

Question: What are tiny filters S known as?
Answer: c

Question: What is (i) organ P, and (ii) waste substance Q?
Answer: a

Question: Name
(i) liquid U
(ii) structure V
(iii) tubes W, and
(iv) tube X.
Answer: d

Question: Name (i) artery R, and (ii) vein T.
Answer: b

Case/Passage – 2

All living cells require energy for various activities. This energy is available by the breakdown of simple carbohydrates either using oxygen or without using oxygen.

Question: The graph below represents the blood lactic acid concentration of an athlete during a race of 400 m and shows a peak at point D.
Lactic acid production has occurred in the athlete while running in the 400 m race.
Respiration in athletics
The blood of an athlete was tested before, during and after a 400m race:

Lactic acid production has occurred in the athlete while running in the 400 m race. Which of the following processes explains this event?
Which of the following processes explains this event?
(a) Aerobic respiration
(b) Anaerobic respiration
(c) Fermentation
(d) Breathing
Answer: b

Question: Study the graph below that represents the amount of energy supplied with respect to the time while an athlete is running at full speed
Choose the correct combination of plots and justification provided in the following table.

Answer: b

Question: The characteristic processes observed in anaerobic respiration are:
(i) presence of oxygen
(ii) release of carbon dioxide
(iii) release of energy
(iv) release of lactic acid
(a) (i), (ii) only
(b) (i), (ii), (iii) only
(c) (ii), iii), iv) only
(d) (iv) only
Answer: c

Question: Energy in the case of higher plants and animals is obtained by
(a) Breathing
(b) Tissue respiration
(c) Organ respiration
(d) Digestion of food
Answer: b

Question: Study the table below and select the row that has the incorrect information.
                                       Aerobic                      Anaerobic
(a) Location                   Cytoplasm                  Mitochondria
(b) End Porduct             CO₂ and H₂O             Ethanol and CO₂
(c) Amount of ATP         High                            Low
(d) Oxygen                    Needed                       Not needed
Answer: a