ICSE 2023 Chemistry Question Paper for Class 10

About this paper

This is the official ICSE Class 10 Chemistry (Science Paper 2) question paper from the 2023 examination, paper code T23 522. It carries 80 marks, with two hours of writing time plus 15 minutes of reading time. Section A (40 marks) is compulsory: Question 1 has 15 one-mark multiple-choice questions, and Question 2 has five five-mark parts, including matching, a sketch of the electrolytic reduction of alumina, terms, and organic formulae and names. In Section B candidates attempt any four of Questions 3–8, worth 10 marks each, covering identifying cations and anions, electrolysis and electro-refining of copper, alloys, a gas-volume problem on burning ethane, ammonia from magnesium nitride and percentage composition. The paper has questions only, without answers.

Exam

ICSE Class 10

Subject

Chemistry

Year

2023

Paper code

T23 522

Maximum marks

80

Time allowed

2 hours + 15 min reading

Questions

8

Pages

11

Answers included

No, questions only

Paper pattern

• Section A – Question 1

  15 marks

  15 multiple-choice questions, one mark each

• Section A – Question 2

  25 marks

  Five five-mark parts: matching, a diagram-based question on aluminium extraction, fill in the blanks, terms, and organic formulae and names

• Section B

  40 marks

  Questions 3–8, attempt any four; 10 marks each

Topics covered

• Periodic table and periodic properties
• Chemical bonding
• Acids, bases and salts
• Analytical chemistry
• Mole concept and stoichiometry
• Electrolysis and electro-refining
• Metallurgy of aluminium and alloys
• Hydrogen chloride
• Ammonia
• Nitric acid
• Sulphuric acid
• Organic chemistry

Questions from this paper

1. State the term for the ratio of the mass of a certain volume of gas to the mass of the same volume of hydrogen measured under the same conditions of temperature and pressure.
2. State a relevant reason why hydrogen chloride gas cannot be dried over quicklime.
3. If 80 ml of ethane is burnt in 300 ml of oxygen according to the equation 2C₂H₆ + 7O₂ → 4CO₂ + 6H₂O, find the composition of the resultant gaseous mixture when measured at room temperature.
4. Write a balanced chemical equation for the laboratory preparation of ammonia from magnesium nitride, and state why this method is seldom used.
5. Calculate the percentage of phosphorus in the fertiliser superphosphate, Ca(H₂PO₄)₂, correct to 1 decimal place. [H = 1, P = 31, O = 16, Ca = 40]
6. With reference to the electro-refining of copper, what is the anode made of and what do you observe at the cathode?