53 practice sets · Page 3 of 3
What type of mixture is sugar dissolved in water?
Suspension
Colloid
Homogeneous mixture
Heterogeneous mixture
Correct Answer: C — Homogeneous mixture
Explanation:
Sugar dissolved in water forms a homogeneous mixture because it is uniformly distributed.
What is a pure substance?
A substance with only one type of molecule
A substance with a mixture of different molecules
A substance that can be separated into two or more components
A substance that is impure
Correct Answer: A — A substance with only one type of molecule
Explanation:
A pure substance contains only one type of particle and cannot be separated by physical methods.
Which of the following substances can exist in all three states of matter?
Nitrogen
Oxygen
Water
Carbon dioxide
Correct Answer: C — Water
Explanation:
Water exists as ice, liquid water, and steam under different conditions.
Which of the following is a chemical property of matter?
Melting point
Hardness
Density
Reactivity with oxygen
Correct Answer: D — Reactivity with oxygen
Explanation:
Reactivity with oxygen is a chemical property because it describes how a substance undergoes chemical change.
What happens to the particles of matter when it is heated?
They move faster
They remain in the same position
They move slower
They change into a different substance
Correct Answer: A — They move faster
Explanation:
Heating increases the kinetic energy of particles, causing them to move faster.
What is the primary source of energy for plants?
Air
Water
Sunlight
Soil
Correct Answer: C — Sunlight
Explanation:
Plants use sunlight to perform photosynthesis.
Which of the following is a property of a chemical reaction?
It always requires heat
It results in the formation of new substances
It only occurs in solids
It only occurs in gases
Correct Answer: B — It results in the formation of new substances
Explanation:
A chemical reaction forms new substances with different properties.
Which of the following is not a property of metals?
Ductile
Malleable
Good conductors of electricity
Poor conductors of heat
Correct Answer: D — Poor conductors of heat
Explanation:
Metals are generally good conductors of heat and electricity.
What is the process of a solid turning directly into a gas called?
Freezing
Melting
Sublimation
Condensation
Correct Answer: C — Sublimation
Explanation:
Sublimation is the direct conversion of a solid into a gas without passing through the liquid state.
Which of the following is not an example of a chemical reaction?
Dissolving salt in water
Burning of wood
Rusting of iron
Digestion of food
Correct Answer: A — Dissolving salt in water
Explanation:
Dissolving salt in water is a physical change because no new substance is formed.
Which of the following is the SI unit of temperature?
Joule
Kelvin
Celsius
Fahrenheit
Correct Answer: B — Kelvin
Explanation:
Kelvin (K) is the SI unit of temperature.
Which organ is responsible for pumping blood in humans?
Brain
Stomach
Heart
Liver
Correct Answer: C — Heart
Explanation:
The heart pumps blood throughout the body.
What is the chemical formula of water?
CO₂
O₂
H₂O
H₂O₂
Correct Answer: C — H₂O
Explanation:
Water has the chemical formula H₂O, consisting of two hydrogen atoms and one oxygen atom.
