3. susan makes the following entry in her notebook: "on friday we were given a blue liquid in a shallow
container, we placed it on the windowsill over the weekend. on monday morning, there was no liquid
left, but the dish had some solid blue stuff in it."
a. was the blue liquid in the dish a heterogeneous mixture, a solution, or a pure substance?
explain your choice.
b. write a few sentences to explain what happened in the dish.

B. Solution

Explanation:

According to the question statement, Susan wrote in her notebook that it was a blue liquid. Therefore, from a chemistry point of view, it was a solution and not a heterogeneous mixture. Then, the solvent was evaporated after leaving the solution for 72 hours at the windowsill. The solute (blue color most likely) however was not able to evaporate with solvent and left behind.

Example: if you leave the KMnO4+water solution for a few days, water will evaporate thus leaving behind purple crystals of KMnO4.

The liquid in the dish is a solution. The solvent in which the blue solid had dissolved was evaporated leaving the solid.

A solution is obtained when a substance, solid. liquid or gas is dissolved in a solvent.

When a solid is dissolved in a solvent in which it is soluble, a solution is formed. A solution is a homogeneous mixture because its components form a single phase.

The fact that the solid could be recovered when the solvent evaporated shows that what we have is a solution of the blue substance in a solvent.

What happened when the over the week end was that the solvent evaporated leaving behind the blue solute.

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the element that provides strength to the exoskeletons of clams and oysters is phosphorus.

this is so because calcium carbonate is the main component in the shells. calcium carbonate is strengthened by phosphorus.

explanation:

hydrogen is a compound or a single element and a element is a pure substence that cannot be separated into simpler subtances

clorine is a compound its a chemical substance that forms when two or more different elements combine

so both hydrogen and clorine are compounds