Unit Test | Metals And Non Metals | Class 10 Science

MG SCHOOL SCIENCE

UNIT TEST – 03

METALS AND NON-METALS

Class 10 | Science | Chemistry

25 MARKS

Board Exam Preparation

Maximum Marks
25

Time Duration
50 Minutes

Total Questions
15

Student Name: ______________________________

Class & Section: ______________ Roll No: __________

Date: ______________________________

GENERAL INSTRUCTIONS

1. All questions are compulsory.
2. Read each question carefully.
3. Write balanced chemical equations wherever necessary.
4. Use appropriate chemical symbols and formulae.
5. Marks are indicated against each question.

SECTION A – MULTIPLE CHOICE QUESTIONS (5 × 1 = 5 Marks)

1. Which of the following metals is stored in kerosene oil? 1 Mark

Iron Copper Sodium Aluminium

Correct answer: (C) Sodium. Sodium reacts vigorously with air and moisture.

2. Which of the following is the most reactive metal? 1 Mark

Gold Potassium Copper Silver

Correct answer: (B) Potassium.

3. Which non-metal is a good conductor of electricity? 1 Mark

Sulphur Phosphorus Graphite Oxygen

Correct answer: (C) Graphite.

4. Which gas is produced when metals react with dilute acids? 1 Mark

Oxygen Hydrogen Nitrogen Carbon dioxide

Correct answer: (B) Hydrogen. Note: The metal must be sufficiently reactive to displace hydrogen from the acid.

5. Which method is used to extract highly reactive metals like sodium? 1 Mark

Reduction with carbon Electrolysis Roasting Heating in air

Correct answer: (B) Electrolysis of molten sodium chloride.

SECTION B – ONE MARK QUESTIONS (4 × 1 = 4 Marks)

6. Define malleability. 1 Mark

The property of metals by which they can be beaten into thin sheets is called malleability.

7. Name the non-metal which is liquid at room temperature. 1 Mark

Bromine.

8. What is an alloy? 1 Mark

An alloy is a homogeneous mixture of two or more metals, or a metal and a non-metal.

9. Name the metal used in galvanisation of iron. 1 Mark

Zinc.

SECTION C – TWO MARK QUESTIONS (3 × 2 = 6 Marks)

10. Why do ionic compounds have high melting and boiling points? 2 Marks

Ionic compounds contain oppositely charged ions held together by strong electrostatic forces of attraction. A large amount of energy is required to overcome these forces, so they have high melting and boiling points.

11. What happens when iron nails are placed in copper sulphate solution? Write the balanced chemical equation. 2 Marks

Iron displaces copper from copper sulphate solution because iron is more reactive than copper. The blue solution turns green and a reddish-brown deposit of copper forms on the nails.

Fe + CuSO₄ → FeSO₄ + Cu

12. Differentiate between metals and non-metals on the basis of any two physical properties. 2 Marks

1. Metals are generally lustrous, whereas non-metals are generally non-lustrous.
2. Metals are generally malleable and ductile, whereas solid non-metals are generally brittle.

SECTION D – THREE MARK QUESTIONS (2 × 3 = 6 Marks)

13. Explain the reaction of metals with oxygen, water and dilute acids with suitable chemical equations. 3 Marks

(a) Reaction with oxygen:
2Mg + O₂ → 2MgO

(b) Reaction with water:
2Na + 2H₂O → 2NaOH + H₂

(c) Reaction with dilute acid:
Zn + 2HCl → ZnCl₂ + H₂

14. Explain the extraction of metals from their ores according to their position in the reactivity series. 3 Marks

1. Highly reactive metals: Extracted by electrolysis of their molten compounds. Example: Sodium.

2. Moderately reactive metals: Their ores are generally converted into oxides by roasting or calcination and then reduced using carbon or carbon monoxide. Example: Zinc.

3. Low reactive metals: Their oxides can often be reduced by heating. Some metals, such as gold, occur in the native state.

SECTION E – FOUR MARK QUESTION (1 × 4 = 4 Marks)

15. Answer the following questions: 4 Marks

(a) What is corrosion? (1 Mark)

(b) What is the chemical name of rust? (1 Mark)

(c) Mention two methods to prevent corrosion of iron. (1 Mark)

(d) Why is aluminium used for making cooking utensils? (1 Mark)

(a) The gradual destruction of metals due to their reaction with air, moisture or chemicals is called corrosion.

(b) Hydrated iron(III) oxide, Fe₂O₃·xH₂O.

(c) Painting and galvanisation. Other acceptable methods include oiling, greasing and electroplating.

(d) Aluminium is a good conductor of heat, is lightweight and forms a protective oxide layer that resists corrosion.

YOUR TEST RESULT

0 / 5

Automatic evaluation covers five MCQs (5 marks). Descriptive answers require teacher evaluation (20 marks).

COMPLETE KEY ANSWERS – TEACHER'S REFERENCE

SECTION A – MCQ ANSWERS
1. C – Sodium
2. B – Potassium
3. C – Graphite
4. B – Hydrogen
5. B – Electrolysis

SECTION B – ONE MARK ANSWERS

6. Malleability: Ability of metals to be beaten into thin sheets.
7. Bromine.
8. An alloy is a homogeneous mixture of two or more metals, or a metal and a non-metal.
9. Zinc.

SECTION C – TWO MARK ANSWERS

10. Strong electrostatic forces between oppositely charged ions require large amounts of energy to overcome.
11. Iron displaces copper from copper sulphate solution. Fe + CuSO₄ → FeSO₄ + Cu.
12. Metals are generally lustrous and malleable, while non-metals are generally non-lustrous and brittle in solid form.

SECTION D – THREE MARK ANSWERS

13. Reaction with oxygen: 2Mg + O₂ → 2MgO.
    Reaction with water: 2Na + 2H₂O → 2NaOH + H₂.
    Reaction with acid: Zn + 2HCl → ZnCl₂ + H₂.
14. Highly reactive metals – electrolysis.
    Moderately reactive metals – reduction of their oxides.
    Low reactive metals – heating or occurrence in native state, depending on the metal.

SECTION E – FOUR MARK ANSWER

15. (a) Corrosion is the gradual destruction of metals by environmental reactions.
    (b) Hydrated iron(III) oxide, Fe₂O₃·xH₂O.
    (c) Painting and galvanisation.
    (d) Aluminium is a good conductor of heat, lightweight and corrosion-resistant due to its protective oxide layer.

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Class 10 Science – Metals and Non-metals