Carbon and its Compound PYQ Class 10

CBSE

1
(a)
(i) Draw two isomeric structures of Butene $(C_{4}H_{8})$.
(ii)

Name the following compounds :

 

(iii)

Write the chemical equations for the following reactions. Mention one essential condition each for these reactions to take place.

(I) Ethanol undergoes complete oxidation

(II) Propene undergoes hydrogenation

(III) Ethanoic acid reacts with ethanol
 

OR
(b)
(i) A carbon compound X is a good solvent. On reaction with sodium, X forms two products Y and Z. Z is used to convert vegetable oil into vegetable ghee. Identify and name X, Y and Z. Also write the equation of reaction of X with sodium to justify your answer.
(ii)

(ii) Write chemical equation to show what happens when ethanol:

(I) burns in oxygen/air.

(II) is heated at 443 K in excess conc. $H_{2}SO_{4}$.

(III) reacts with acidified potassium dichromate.

[5 marks]

2

Carbon compounds:

(i) are good conductors of electricity.

(ii) are bad conductors of electricity.

(iii) have strong forces of attraction between their molecules.

(iv) have weak forces of attraction between their molecules.

The correct statements are:

[1 marks]

3
(A)
(i) Define a homologous series of carbon compounds.
(ii) Why is the melting and boiling points of $\ce{C4H8}$ higher than that of $\ce{C3H6}$ or $\ce{C2H4}$?
(iii) Why do we NOT see any gradation in chemical properties of a homologous series compounds ?
(iv) Write the name and structures of (i) aldehyde and (ii) ketone with molecular formula $\ce{C3H6O}$.
  OR
(B)
(i) Write the name and structure of an organic compound 'X' having two carbon atoms in its molecule and its name is suffixed with '-ol'.
(ii) What happens when 'X' is heated with excess concentrated sulphuric acid at 443 K? Write chemical equation for the reaction stating the conditions for the reaction. Also state the role played by concentrated sulphuric acid in the reaction.
(iii)

Name and draw the electron dot structure of hydrocarbon produced in the above reaction.

 

[5 marks]

4

Consider the structures of the three cyclic carbon compounds A, B and C given below and select the correct option from the following:

Question

[1 mark]

5

(a) A saturated organic compound 'A' belongs to the homologous series of alcohols. On heating 'A' with concentrated sulphuric acid at 443 K, it forms an unsaturated compound 'B' with molecular mass 28 u. The compound 'B' on addition of one mole of hydrogen in the presence of Nickel, changes to a saturated hydrocarbon 'C'.

(i) Identify A, B and C.

(ii) Write the chemical equations showing the conversion of A into B.

(iii) What happens when compound C undergoes combustion?

(iv) State one industrial application of hydrogenation reaction.

(v) Name the products formed when compound A reacts with sodium.

OR

(b) (i) With the help of diagram, show the formation of micelles, when soap is applied on oily dirt.

(ii) Take two test tubes X and Y with 10 mL of hard water in each. In test tube 'X', add few drops of soap solution and in test tube Y add a few drops of detergent solution. Shake both the test tubes for the same period.

(1) In which test tube the formation of foam will be more ? Why?

(2) In which test tube is a curdy solid formed? Why?

[5 marks]

6
(a)

Write the molecular formula of the following carbon compounds :

  1. Methane
  2. Propane
(b) Carbon compounds have low melting and boiling points. Why?

[2 marks]

7
(a)

 Draw two different possible structures of a saturated hydrocarbon having four carbon atoms in its molecule. What are these two structures of the hydrocarbon having same molecular formula called? Write the molecular formula and the common name of this compound. Also write the molecular formula of its alkyne.
  OR
(b)
(i)

Write the molecular formula of benzene and draw its structure.
(ii)

Write the number of single and double covalent bonds present in a molecule of benzene.
(iii)

Which compounds are called alkynes ?

[3 marks]