Test Your Knowledge for Chapter 8–Nature of Matter: Elements, Compounds, and Mixtures in the form of MCQs
Multiple Choice Questions:
1. What is a mixture?
A) A pure substance made of one element
B) Combination of substances that react chemically
C) Combination of two or more substances retaining their properties
D) New compound formed by elements
Answer: C) Combination of two or more substances retaining their properties
2. Which of the following is a uniform mixture?
A) Sprout salad
B) Sugar dissolved in water
C) Sand and salt mixture
D) Iron and sulfur
Answer: B) Sugar dissolved in water
3. What are the substances that make up a mixture called?
A) Compounds
B) Elements
C) Components
D) Molecules
Answer: C) Components
4. Which of the following is a non-uniform mixture?
A) Air
B) Lemonade
C) Soil
D) Vinegar
Answer: C) Soil
5. Air is a —
A) Compound
B) Non-uniform mixture
C) Uniform mixture
D) Pure substance
Answer: C) Uniform mixture
6. Which of the following mixtures is an alloy?
A) Brass
B) Sand and water
C) Milk and water
D) Air
Answer: A) Brass
7. A pure substance has —
A) Different types of particles
B) Identical particles
C) Air particles
D) Both solids and gases
Answer: B) Identical particles
8. What is an element?
A) Substance that can be broken into simpler ones
B) Mixture of compounds
C) Simplest pure substance made of one kind of atom
D) A non-pure substance
Answer: C) Simplest pure substance made of one kind of atom
9. Which of the following is a compound?
A) Nitrogen
B) Sulfur
C) Water
D) Iron
Answer: C) Water
10. What is formed when hydrogen and oxygen combine chemically in a fixed ratio?
A) Air
B) Water
C) Hydrogen peroxide
D) Hydrogen sulfide
Answer: B) Water
More:
11. The elements in a compound are combined —
A) Randomly
B) In fixed ratio
C) By physical means
D) Without chemical change
Answer: B) In fixed ratio
12. Which one is NOT a pure substance?
A) Sugar
B) Salt
C) Air
D) Iron
Answer: C) Air
13. The process of passing electricity through water gives —
A) Hydrogen and oxygen
B) Carbon dioxide
C) Nitrogen and hydrogen
D) Steam only
Answer: A) Hydrogen and oxygen
14. Iron sulfide is a —
A) Mixture
B) Compound
C) Element
D) Solution
Answer: B) Compound
15. The gas with a ‘pop’ sound during testing is —
A) Oxygen
B) Hydrogen
C) Nitrogen
D) Carbon dioxide
Answer: B) Hydrogen
16. Which gas turns lime water milky?
A) Oxygen
B) Carbon dioxide
C) Nitrogen
D) Hydrogen
Answer: B) Carbon dioxide
17. Brass is made of —
A) Iron and carbon
B) Copper and zinc
C) Copper and tin
D) Silver and gold
Answer: B) Copper and zinc
18. Stainless steel is a mixture of —
A) Iron, nickel, chromium
B) Iron and carbon
C) Zinc and copper
D) Aluminium and sulfur
Answer: A) Iron, nickel, chromium
19. Which of the following is NOT matter?
A) Air
B) Light
C) Water
D) Soil
Answer: B) Light
20. Which of the following minerals is a pure element?
A) Quartz
B) Mica
C) Gold
D) Calcite
Answer: C) Gold
Fill in the Blanks:
21. A __________ is formed when two or more substances mix without chemical reaction.
A) Compound B) Mixture C) Solution D) Solvent
Answer: B) Mixture
22. Components of a mixture retain their __________.
A) New properties B) Original properties C) Colour D) Shape
Answer: B) Original properties
23. The components of a mixture can be separated by __________ methods.
A) Chemical B) Physical C) Magnetic D) Heat
Answer: B) Physical
24. A pure substance has __________ type of particles.
A) Many B) Same C) Two D) None
Answer: B) Same
25. Elements combine in __________ ratio to form a compound.
A) Fixed B) Changing C) Variable D) Random
Answer: A) Fixed
26. Water is a compound of hydrogen and __________.
A) Nitrogen B) Oxygen C) Carbon D) Sulfur
Answer: B) Oxygen
27. Brass is a mixture of copper and __________.
A) Zinc B) Tin C) Iron D) Lead
Answer: A) Zinc
28. The gas that makes lime water turn milky is __________.
A) Oxygen B) Hydrogen C) Carbon dioxide D) Nitrogen
Answer: C) Carbon dioxide
29. The soft metal that combines with chlorine to form common salt is __________.
A) Sodium B) Iron C) Magnesium D) Zinc
Answer: A) Sodium
30. Substances like gold and silver found naturally are called __________.
A) Mixtures B) Minerals C) Rocks D) Alloys
Answer: B) Minerals
True or False:
31. A mixture is a chemical combination of substances. — False
32. Air is a uniform mixture of gases. — True
33. Pure substances can be separated by physical means. — False
34. Water is a compound of hydrogen and oxygen. — True
35. Brass is an element. — False
36. Sulfur and iron mixture can be separated using a magnet. — True
37. Iron sulfide can be separated by physical methods. — False
38. Elements are the simplest form of matter. — True
39. Light and heat are forms of matter. — False
40. All minerals are mixtures of elements. — False
Match the Following :
| Column A | Column B |
|---|---|
| 1. Element | a) Simplest pure substance |
| 2. Compound | b) Chemically combined elements |
| 3. Mixture | c) Physically combined substances |
| Answer: 1–a, 2–b, 3–c |
| Column A | Column B |
|---|---|
| 1. Brass | a) Copper + Zinc |
| 2. Water | b) Hydrogen + Oxygen |
| 3. Stainless steel | c) Iron + Nickel + Chromium |
| Answer: 1–a, 2–b, 3–c |
| Column A | Column B |
|---|---|
| 1. Air | a) Mixture of gases |
| 2. Gold | b) Pure element |
| 3. Quartz | c) Mineral compound |
| Answer: 1–a, 2–b, 3–c |
Assertion–Reason Questions:
1. Assertion (A): Air is a mixture.
Reason (R): Its components do not react chemically with one another.
A) Both A and R are true, and R is the correct explanation of A.
B) Both A and R are true, but R is not the correct explanation of A.
C) A is true, but R is false.
D) A is false, but R is true.
Answer: A) Both A and R are true, and R is the correct explanation of A.
2. Assertion (A): Water can be separated into hydrogen and oxygen by physical means.
Reason (R): Compounds can be broken down only by chemical means.
A) Both A and R are true, and R is the correct explanation of A.
B) Both A and R are true, but R is not the correct explanation of A.
C) A is false, but R is true.
D) Both A and R are false.
Answer: C) A is false, but R is true.
To Learn more Click Below:
MCQs:
Chapter 1- Exploring the Investigative World of Science – CLICK HERE
Chapter 2- The Invisible Living World: Beyond Our Naked Eye – CLICK HERE
Chapter 3- Health: The Ultimate Treasure – CLICK HERE
Chapter 4-Electricity: Magnetic and Heating Effects – CLICK HERE
Chapter 5- Exploring Forces – CLICK HERE
Chapter 6- Pressure, Winds, Storms, and Cyclones – CLICK HERE