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Question 1:

What is the process called when a substance changes directly from a solid to a gas without going through the liquid phase?

A) Melting
B) Sublimation
C) Freezing
D) Condensation

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Explanation: The correct answer is B) Sublimation. Sublimation is the process in which a substance changes directly from the solid phase to the gaseous phase without going through the liquid phase. It occurs when the temperature and pressure conditions allow the solid to vaporize without melting.

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Question 2:

Which of the following is an example of sublimation?

A) Ice melting into water
B) Water freezing into ice
C) Dry ice turning into carbon dioxide gas
D) Steam condensing into water droplets

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Explanation: The correct answer is C) Dry ice turning into carbon dioxide gas. Dry ice, which is solid carbon dioxide, undergoes sublimation when it changes directly from the solid phase to the gaseous phase without melting into a liquid. This process is commonly observed with dry ice.

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Question 3:

What is the process called when a gas changes directly into a solid without going through the liquid phase?

A) Melting
B) Sublimation
C) Freezing
D) Deposition

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Explanation: The correct answer is D) Deposition. Deposition is the process in which a gas changes directly into a solid without going through the liquid phase. It occurs when the temperature and pressure conditions allow the gas to solidify without condensing into a liquid state.

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Question 4:

Which of the following is an example of deposition?

A) Ice melting into water
B) Water freezing into ice
C) Dry ice turning into carbon dioxide gas
D) Water vapor forming frost ona cold surface

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Explanation: The correct answer is D) Water vapor forming frost on a cold surface. Deposition occurs when water vapor changes directly into a solid without going through the liquid phase. This process is commonly observed when water vapor in the air comes into contact with a cold surface and forms frost.

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Question 5:

Which phase transition involves the absorption of energy from the surroundings?

A) Melting
B) Sublimation
C) Freezing
D) Condensation

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Explanation: The correct answer is B) Sublimation. Sublimation is an endothermic process that involves the absorption of energy from the surroundings to change a substance directly from the solid phase to the gaseous phase. It requires the addition of heat to overcome the intermolecular forces and break the solid structure.