Question

surname:
q.14. when the particles are ____________, they gain energy and move faster.
a) heated b) cooled
q.15. which state of matter has the most energy?
a) solid b) liquid c) gas
q.16. which of the following does not take the shape of its container?
a) gasoline b) pencil
c) oxygen d) juice
q.17. what is the name of the process when a gas turns into a liquid?
a) melting b) evaporation
c) condensation d) freezing
q.18. what is the name of the process when a liquid turns into a solid?
a) melting b) evaporation
c) condensation d) freezing
q.19. what is the name of the process when a solid turns directly into a gas?
a) sublimation b) deposition
c) evaporation d) condensation
q.20. a matter has a melting point of -25 °c, and a boiling point of 46 °c. what state will it have at a temperature of 53 °c?
a) solid b) liquid c) gas
q.21. a matter has a melting point of 10 °c, and a boiling point of 95 °c. what state will it have at a temperature of 53 °c?
a) solid b) liquid c) gas
q.22. the table shows the melting points and boiling points for different substances. identify the state of given substances at room temperature (room temperature is around 20°c).
water: melting point (°c) 0, boiling point (°c) 100, state at room temperature
oxygen: melting point (°c) -218, boiling point (°c) -183, state at room temperature
iron: melting point (°c) 1538, boiling point (°c) 2861, state at room temperature
sulfuric acid: melting point (°c) 10.3, boiling point (°c) 337, state at room temperature
magnesium: melting point (°c) 650, boiling point (°c) 1090, state at room temperature
nitrogen: melting point (°c) -210, boiling point (°c) -195, state at room temperature

Explanation:

For Q.14: Heating particles gives them energy to move faster. Cooling does the opposite.
For Q.15: Gas particles have the most energy as they move freely and rapidly compared to solids (least energy) and liquids.
For Q.16: Solids (like pencil) have a fixed shape. Liquids (gasoline, juice) take container shape and gases (oxygen) also fill the container.
For Q.17: Condensation is gas to liquid. Melting is solid to liquid, evaporation liquid to gas, freezing liquid to solid.
For Q.18: Freezing is liquid to solid.
For Q.19: Sublimation is solid to gas directly. Deposition is gas to solid directly.
For Q.20: At 53°C (above boiling point 46°C), it's gas.
For Q.21: At 53°C (above melting point 10°C and below boiling point 95°C), it's liquid.
For Q.22:

• Water: 0 (melting) < 20 < 100 (boiling) → liquid.
• Oxygen: -183 (boiling) < 20 → gas (already boiled off).
• Iron: 20 < 1538 (melting) → solid.
• Sulfuric acid: 10.3 (melting) < 20 < 337 (boiling) → liquid.
• Magnesium: 20 < 650 (melting) → solid.
• Nitrogen: -195 (boiling) < 20 → gas (already boiled off).

Answer:

Q.14: a) heated
Q.15: c) Gas
Q.16: b) Pencil
Q.17: c) Condensation
Q.18: d) Freezing
Q.19: a) Sublimation
Q.20: c) gas
Q.21: b) liquid
Q.22:

• Water: liquid
• Oxygen: gas
• Iron: solid
• Sulfuric acid: liquid
• Magnesium: solid
• Nitrogen: gas