Kerala Syllabus Class 10 Chemistry Model Question Paper Set 4

Practicing Chemistry Question Paper Class 10 Kerala Syllabus Set 4 English Medium helps identify strengths and weaknesses in a subject.

Chemistry Class 10 Kerala Syllabus Model Question Paper Set 4

Time: 1½ Hours
Score: 40 Marks

Instructions:

1. First 15 minutes is given as cool.of time.
2. This time is to be spent for reading the question paper.
3. Answer according to the instructions
4. Answer the questions considering the score and time.

I. Answer any 4 Questions from 1 to 5. Each carries 1 Score. (4 × 1 = 4)

Question 1.
To which block of the periodic table does the transition elements
Answer:
d. block

Question 2.
Find out the relation and fill up
Calcination : Zn CO₃
………….. : Cu₂S
Answer:
Roasting

Question 3.
H₂ S₂ O₇ is a compound formed during contact process. It is also known as ………..
Answer:
Oleum

Question 4.
4 gram helium contains 6.022 × 10²³ atoms. What is this number called?
Answer:
Avogadro number

Question 5.
Choose the compound which undergoes addition reaction
(Ethene, Ethane, Methane, Propane)
Answer:
Ethene

II. Answer any 4 Questions from 6 to 10. Each carries 2 Score. (4 × 2 = 8)

Question 6.
Atomic number of Mn is 25. Based on this, answer the questions given below
a) What is the oxidation state of Mn in MnCl₂.
b) Write the subshell electronic configuration of Mn ion in MnCl₂
Answer:
a) 2
b) 1s² 2s² 2p⁶ 3s² 3p⁶ 3d⁵

Question 7.
Among the metals Copper, Aluminium, Gold which one loses its metallic lusture quickly?
Write the equation for the chemical reaction
Answer:
a) Al
b) 4 Al +3 O₂ → 2 Al₂ O₃

Question 8.
Chemical equation for the identification of the salt is given below.
Na₂ SO₄ + x → BaSO₄ +2 NaCl
a) What is ‘X’
b) Which is the substance precipitated here?
Answer:
a) BaCl₂
b) Ba SO₄

Question 9.
Molecular formula of some compounds are given below
P) C₃ H₆
R) C₃H₈
S) C₄H₈
a) Which one is alkane?
b) Write the general formula of the hydrocarbon to which the compound ‘Q belongs?
Answer:
a) C₃H₈
b) C_nH₂

Question 10.
Analyse the given figure and answer the following questions

a) What pressure must be applied to change the volume of the gas into 1,L at constant emperature.
b) Write the gas law related to it
Answer:
a) 2 atm
b) Boyle’s law

III. Answer any 4 Questions from 11 to 15 Each carries 3 Score. (4 × 3 = 12)

Question 11.
Alumic number of X is 19 and the at nic number of Y is 8.
Write the sub shell electronic conform, ration of the element X
b) Write the group number of the element Y?
c) Write the chemical formula for a compound formed by combining X and Y
Answer:
a) 1s² 2s² 2p⁶ 3s² 3p⁶ 4s¹
b) Group number = 16
c) X₂Y

Question 12.
A reversible reaction is given below
N₂(g) + 3H₂(g) ⇌ 2 NH₃(g) + Heat
How does the following factors influence the quantity of the product in the chemical reaction.
a) Pressure increases
b) Remove NH
c) Increases the amount of hydrogen
Answer:
a) Increases the amount of product
b) Increases the amount of product
c) Increases the amount of product

Question 13.
Sodium hydroxide is formed as a byproduct during the electrolysis of sodium chloride solution
a) Which is the gas formed in positive electrode?
b) Write the equations for the oxidation and reduction reaction of the cell
c) What is the difference between the energy change in galvanic cell and electrolytic cell.
Answer:
a) Chlorine
b) 2Cl → Cl₂ + 2e^–, 2 H₂O + 2e^– → H₂ + 2 OH^–
c) Galvanic cell – Chemical energy changes do electrical energy
Electrolytic cell – Electrical energy changes to chemical energy

Question 14.
Ester is formed by the reaction of carboxylic acid and alcohol.
a) write the name of the carboxylic acid which is required to form methyl ethanoyate.
b) Write the chemical equation for the preparation of methyl ethanoyate
Answer:
a) Ethanoic acid
b) CH₃ – COOH+ HO – CH₃ → CH₃ – COO – CH₃ + H₂O

Question 15.
The IUPAC names of three organic compounds are given below. Draw their structure.
a) 2, 4 – dimethyl hexane
b) But – 1 – ene
c) Propanoic acid
Answer:

b) CH₂ = CH – CH₂ – CH₃
c) CH₃ – CH₂ – COOH

IV. Answer any 4 Questions from 16 to 20. Each carries 3 Score. (4 × 4 = 16)

Question 16.
SO₂ and NO₂ are two gases with same volume occupy at STP.
(Atomic Mass S = 32, O = 16, N = 14)
At STP (i) 320 g SO₂, (ii) „A… g NO₂ samples are taken
(a) Find out the value of A.
(b) Write the number of molecules in 320 g SO₂
(c) What is the volume of these two samples?
Answer:
a) 230 g
b) Number of moles = 320/₆₄ = 5
Number of molecules = 5 × 6.022 × 10²³
c) 5 mole = 5 × 22.4 L = 112 L

Question 17.
Two incomplete chemical equations are given below.
i) CH₃ – CH₂ – CH₂ – CH₃ → CH₃ – CH₃ + P
ii) P + H₂ → Q
a) Write the real structure of P and Q.
b) Write the names of the chemical reactions (i) and (ii)
Answer:
a) P-CH₂ = CH₂
Q – CH₃ – CH₃
b) i) Thermal Cracking ii) Addition reaction

Question 18.
Analyse the following figure and Answer the questions.

a) What are the changes occur in iron rod and copper sulphate solution?
b) Write the equation for oxidation reaction?
c) Is there any change occur when silver rod is used instead of iron. Give reason.
Answer:
a) Colour of the copper sulphate solution fades. Copper clings on the iron rod
b) Fe → Fe²⁺ + 2e^–
c) No, Reactivity of silver is less than that of copper

Question 19.
Aluminium is prepared by the electrolysis of alumina which is mixed with cryolite.
a) Write the chemical formula of alumina
b) What is the purpose of adding cryolyte in alumina?
c) At which electrode aluminium is formed? Write the equation for the chemical reaction takes place in this electrode.
Answer:
a) Al₂ O₃
b) To decrease the melting point and increase the conductivity of alumina
c) Cathode, Al³⁺ + 3e^– → Al

Question 20.
Isomers are compounds with same molecular formula but different structural formula.
a) Write the structural formula of an alcohol and an ether with molecular formula C₃H₈O.
b) Write the IUPAC name of the ether with molecular formula C₃H₈O
c) Which type of isomers are they?
Answer:

b) Methoxy ethane
c) Functional isomers