Question

1. which one of these is not a way to form crystals?

• cooling a liquid from a melt
• forming a precipitate from a chemical reaction
• warming a solid until it melts
• cooling or evaporating a solution

1. how did the monoclinic sulfur crystals grow?

• cooling a liquid from a melt
• forming a precipitate from a chemical reaction
• warming a solid until it melts
• cooling or evaporating a solution

1. what was the solute in the single, blue crystals you grew?

• copper sulfate
• borax
• gypsum
• sugar

Explanation:

Question 43

To determine which is not a way to form crystals, we analyze each option:

• Cooling a liquid from a melt: This can form crystals (e.g., freezing water to ice or forming minerals from magma).
• Forming a precipitate from a chemical reaction: Precipitates can be crystalline (e.g., silver chloride precipitate).
• Warming a solid until it melts: Melting a solid is the reverse of forming crystals; it breaks the crystal structure, so this is not a way to form crystals.
• Cooling or evaporating a solution: Evaporation (e.g., salt from seawater) or cooling (e.g., sugar crystals from syrup) can form crystals.

Monoclinic sulfur crystals grow by cooling a liquid from a melt. When sulfur is melted and then cooled, the liquid sulfur (from the melt) can crystallize into monoclinic sulfur.

• Forming a precipitate from a chemical reaction: Not the method for monoclinic sulfur growth.
• Warming a solid until it melts: This is melting, not crystal growth.
• Cooling or evaporating a solution: Monoclinic sulfur isn't typically grown this way (it's from melt cooling).

Copper sulfate forms blue crystals. Borax crystals are usually white/colorless, gypsum is white/colorless, and sugar crystals are white. So the solute in the single, blue crystals grown is copper sulfate.

Answer:

The option "warming a solid until it melts" is not a way to form crystals. So the correct option is the one with "warming a solid until it melts".

Question 44