What are some examples of physical properties? What are some examples of chemical properties?
What is a physical change?
What are some examples of physical changes?

Physical properties: how soft a blanket it, how hard bread is, what color leaves are, what bleach smells like.

Chemical change: burning wood, rotting food, digestion, rusting of a nail.

Physical change: mixing salt and sugar, tearing a piece of paper, melting ice, chopping wood.

Explanation:

Physical properties are properties that are measurable.

Chemical change is when substances combine (fire and wood make burning wood) to make another substance. They aren't reversible. If you were to melt ice, you could refreeze it, you can't unburn wood.

Physical change is something that alters the form of the substance but not the chemical composition.

Hope this helps!

your answer is a. the enthalpy of formation for a pure element in its standard state is always positive.