Question

what must happen to the particles of a solid to allow it to become a liquid? *
particles move further apart, allowing the substance to melt
particles move further apart, allowing the substance to evaporate
particles move closer together, allowing the substance to freeze
particles move closer together, allowing the substance to condense
which of the following substances is an element? *
water
orange juice
air
gold
dry ice, or solid carbon dioxide, is used for a number of tasks including food preservation and special effects. the \fumes\ are caused by the carbon dioxide gas being formed directly from solid carbon dioxide. what change of state is this representing?
deposition

Explanation:

• For the first question: In a solid, particles are closely packed. When a solid melts to become a liquid, the particles gain energy and move further apart. Evaporation is liquid to gas, freezing is liquid to solid (particles move closer), and condensation is gas to liquid (particles move closer).
• For the second question: An element is a pure substance made of only one type of atom. Water (\(H_2O\)) is a compound, orange juice is a mixture, air is a mixture (contains \(N_2\), \(O_2\) etc.), and gold (\(Au\)) is an element.

Answer:

• First question: Particles move further apart, allowing the substance to melt.
• Second question: gold.