CBSE Class 10 Science Sample Paper 2023

SECTION - A

Select and write one most appropriate option out of the four options given for each of the questions

Q. No Questions Marks
1 The change in colour of the moist litmus paper in the given set up is due to 

i. presence of acid
ii. presence of base
iii. presence of H⁺(aq) in the solution
iv. presence of Litmus which acts as an indicator
(a) i and ii
(b) Only ii
(c) Only iii
(d) Only iv.

Answer : C

2 In the redox reaction
MnO2 + 4HCl → MnCl2 + 2H2O + Cl2
(a) MnO2 is reduced to MnCl2& HCl is oxidized to H2O
(b) MnO2 is reduced to MnCl2& HCl is oxidized to Cl2
(c) MnO2 is oxidized to MnCl2 & HCl is reduced to Cl2
(d) MnO2 is oxidized to MnCl2 & HCl is reduced to H2O

Answer : B

3

 
Which of the following is the correct observation of the reaction shown in the above set up?
(a) Brown powder of Magnesium oxide is formed.
(b) Colourless gas which turns lime water milky is evolved.
(c) Magnesium ribbon burns with brilliant white light.
(d) Reddish brown gas with a smell of burning Sulphur has evolved.

Answer : C

4 With the reference to four gases CO2,CO, Cl2 and O2, which one of the options in the table is correct? 

Answer : B

5 On placing a copper coin in a test tube containing green ferrous sulphate solution, it will
be observed that the ferrous sulphate solution
(a) turns blue, and a grey substance is deposited on the copper coin.
(b) turns colourless and a grey substance is deposited on the copper coin.
(c) turns colourless and a reddish–brown substance is deposited on the copper coin.
(d) remains green with no change in the copper coin.

Answer : D

6 Anita added a drop each of diluted acetic acid and diluted hydrochloric acid on pH paper and compared the colors. Which of the following is the correct conclusion?
(a) pH of acetic acid is more than that of hydrochloric acid.
(b) pH of acetic acid is less than that of hydrochloric acid.
(c) Acetic acid dissociates completely in aqueous solution.
(d) Acetic acid is a strong acid

Answer : A

7 The formulae of four organic compounds are shown below. Choose the correct option

(a) A and B are unsaturated hydrocarbons
(b) C and D are saturated hydrocarbons
(c) Addition of hydrogen in presence of catalyst changes A to C
(d) Addition of potassium permanganate changes B to D

Answer : C

8 In the given transverse section of the leaf identify the layer of cells where maximum photosynthesis occurs.

(a) I, II
(b) II, III
(c) III, IV
(d) I, IV

Answer : B

9 Observe the experimental setup shown below. Name the chemical indicated as ‘X’ that can absorb the gas which is evolved as a byproduct of respiration.
(a) NaOH
(b) KOH
(c) Ca (OH)2
(d) K2CO3

Answer : B