What is a substance that cannot be separated into simpler substances by physical or mechanical methods such as filtering, boiling, or sifting?

A crystalline solid
A sublimation
A pure substance ••
An amorphous solid

Correct me if I'm wrong

6 answers

You are correct :)
I agree
What is the flipping answer.
A crystalline solid
what is the eeefing answer.
A crystalline solid