When a single salt crystal is added to a cool liquid, large crystals form. Which statement about the original cool liquid is correct?

Question

• The liquid is a pure substance because it was made up of a single compound.
• The liquid is a pure substance because it was uniform before the crystal was added.
• The liquid is a heterogeneous mixture because the crystals can be easily separated from the liquid.
• The liquid is a homogeneous mixture because the substance that formed the large crystals was uniformly dissolved.

Answer 1

The correct statement about the original cool liquid is:

• The liquid is a homogeneous mixture because the substance that formed the large crystals was uniformly dissolved.

This choice is accurate because a homogeneous mixture (or solution) appears uniform throughout, meaning that the solute (in this case, the salt) is evenly distributed in the solvent (the liquid). When the salt crystal is added, it can dissolve and lead to the formation of large crystals upon cooling, indicating that the initial liquid was indeed a homogeneous solution.