Asubstance with a hardness of 8 will scratch a substance with a hardness of 7.

True

Explanation:
Hardness is defined as the ability of a substance to resist being scratched. It can be described using Moh's scale

From the given, we can note that the material with hardness 8 has more resistance to being scratched that a material with hardness 7.

This means that if these two substances came in contact, the more hard substance will scratch the less hard substance.

Hope this helps :)

Must be negative.substance increases