Question

A student heated a blue copper sulfate crystal in a test tube. After a few minutes, she observed that the crystal turned white and the inside of the test tube was covered with a thin film of water. The water inside the test tube most likely __.
Multiple choice question.

seeped through the sides of the test tube


was left from cleaning the test tube the night before


condensed from the air around the test tube


came from the blue copper sulfate crystal, which is a hydrate

Answer 1

The water from inside the test tube most likely came from the blue copper sulfate crystal which is a hydrated salt.

Hydrated salts

Hydrated salts contain water of hydration.

A blue copper sulfate crystal contains water of hydration.

When heated, the water evaporates off to give an anhydrous salt which appears colorless.

The equation of the reaction is as follows:

CuSO4•5H2O -----> CuSO4 + 5H2O(g)

More on water of hydration can be found here: brainly.com/question/919417