1. Which of the following is a physical change
A) Burning of paper
B) Rusting of iron
C) Melting of ice
D) Cooking food
2. Which of the following is a chemical change
A) Burning coal
B) Boiling water
C) Dissolving sugar
D) Breaking glass
3. Matter is defined as anything that has
A) Shape only
B) Volume only
C) Color
D) Mass and occupies space
4. Which state of matter has definite shape and volume
A) Liquid
B) Solid
C) Gas
D) Plasma
5. Which state of matter has no definite shape but definite volume
A) Solid
B) Gas
C) Liquid
D) Plasma
6. Which state of matter has neither definite shape nor volume
A) Gas
B) Solid
C) Liquid
D) Plasma
7. An element is a substance made of
A) Different atoms
B) Same kind of atoms
C) Molecules only
D) Compounds
8. A compound is formed by
A) Physical mixing
B) Separation
C) Filtration
D) Chemical combination
9. Mixtures can be separated by
A) Physical methods
B) Chemical reaction
C) Heating only
D) Burning
10. The smallest unit of an element is
A) Molecule
B) Electron
C) Atom
D) Proton
11. The center of an atom is called
A) Electron
B) Nucleus
C) Neutron
D) Shell
12. Which particle has negative charge
A) Proton
B) Neutron
C) Nucleus
D) Electron
13. Which particle has no charge
A) Neutron
B) Proton
C) Electron
D) Ion
14. Acids taste
A) Sweet
B) Bitter
C) Sour
D) Salty
15. Litmus turns red in
A) Base
B) Acid
C) Salt
D) Water
16. pH value less than 7 indicates
A) Acid
B) Base
C) Neutral
D) Salt
17. Common salt is chemically
A) NaOH
B) HCl
C) CaCO₃
D) NaCl
18. Which metal is liquid at room temperature
A) Iron
B) Mercury
C) Copper
D) Aluminium
19. Non-metals are generally
A) Conductors
B) Ductile
C) Brittle
D) Malleable
20. The valency of carbon is
A) 2
B) 3
C) 1
D) 4
21. Which gas is produced by burning carbon
A) Oxygen
B) Nitrogen
C) Carbon dioxide
D) Hydrogen
22. Periodic table is arranged by
A) Atomic number
B) Mass only
C) Size
D) Density
23. Elements in same group have
A) Same mass
B) Same size
C) Same color
D) Same properties
24. The main gas in air is
A) Nitrogen
B) Oxygen
C) Carbon dioxide
D) Hydrogen
25. Water is a
A) Element
B) Mixture
C) Compound
D) Gas
26. Freezing point of water is
A) 10°C
B) 0°C
C) 5°C
D) -5°C
27. Which gas is essential for breathing
A) Nitrogen
B) Carbon dioxide
C) Hydrogen
D) Oxygen
28. Hard water contains
A) Calcium and magnesium salts
B) Sodium salts
C) Potassium salts
D) Iron salts
29. Which acid is present in lemon
A) Acetic acid
B) Citric acid
C) Hydrochloric acid
D) Sulfuric acid
30. Which base is used in soap
A) NaOH
B) NaCl
C) HCl
D) CO₂
31. Which gas turns limewater milky
A) Oxygen
B) Hydrogen
C) Nitrogen
D) Carbon dioxide
32. Which metal reacts with water vigorously
A) Copper
B) Sodium
C) Iron
D) Silver
33. Which non-metal is essential for life
A) Sulfur
B) Phosphorus
C) Carbon
D) Chlorine
34. Which substance is used to neutralize acid
A) Base
B) Acid
C) Salt
D) Water
35. Which is an example of mixture
A) Water
B) Salt
C) Sugar
D) Air