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2 years ago

Which of these are physical changes in matter chech all that apply

Chemistry

2 answers:

Bogdan [553]2 years ago

8 0

Explanation:

Changes that are unable to bring any difference in chemical composition of a substance are known as physical change.

For example, change in shape, size, mass, volume, density, boiling or freezing point etc are all physical changes.

Whereas changes that bring difference in chemical composition of a substance are known as chemical changes.

For example, reactivity, toxicity, combustion etc are all chemical changes.

Hence, out of the given options physical changes are classified as follows.

Boiling water

A pencil being sharpened

Freezing water

serious [3.7K]2 years ago

6 0

Answer:

a pencil being sharpened

freezing water

boiling water

Explanation:

a physical change doesn't change the chemical structure of an object. That is why the other 2 are wrong

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And as the molar mass of the HgS is $232.66\frac{g}{mol}$ you can calculate the mass of HgS that is produced:

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