Dissolving & Solutions

Question 1

Sam mixes 2 tablespoons of powdered orange drink mix into a cup of warm water until the water looks clear. He wants to get the orange crystals back so he can use them later. Which of the following procedures will correctly recover the crystals by evaporation?

Accepted Answer

Spread the mixture in a shallow dish and leave it in a sunny spot until all the water evaporates, leaving the crystals behind.

Answer

Pour the mixture through a kitchen strainer to catch the crystals while the water drains away.

Answer

Place the cup in the freezer until the water turns to ice, then remove the ice and keep the crystals.

Answer

Heat the mixture on the stove until it boils, then quickly capture the steam in a bowl.

Question 2

Lila adds 3 teaspoons of powdered lemonade mix to a cup of warm water and stirs. The liquid becomes clear with no visible particles. She then leaves the cup uncovered on the kitchen counter. After a few hours a thin white layer forms on the bottom of the cup. Which statement correctly explains what happened?

Accepted Answer

The lemonade mix dissolved completely, forming a solution; as the water evaporated, the dissolved powder re‑crystallized as a white layer.

Answer

The lemonade mix did not dissolve; the white layer is the undissolved powder that settled.

Answer

The lemonade mix turned into a gas when heated and later condensed as a white layer.

Answer

The water turned into ice, trapping the powder as a white layer.

Question 3

Maya adds 2 teaspoons of powdered lemonade mix to a cup of cold water and stirs. Some of the powder stays at the bottom. She then gently heats the cup on the stove until the water is steaming, and all of the powder disappears. After the water cools to room temperature, it looks clear with no visible particles. Which statement best describes the liquid Maya now has?

Accepted Answer

It is a solution because the solid has completely dissolved and the liquid is clear.

Answer

It is a mixture because some powder was visible before heating.

Answer

It is a suspension because the tiny particles are still present even though they cannot be seen.

Answer

It is a colloid because the particles are so small they are invisible.

Try three questions

Sam mixes 2 tablespoons of powdered orange drink mix into a cup of warm water until the water looks clear. He wants to get the orange crystals back so he can use them later. Which of the following procedures will correctly recover the crystals by evaporation?

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