What is the most important thing you need to remember for physical change?

The most important thing you need to know about physical change, is that a physical change does not change the identity, or chemical make up of an object or substance. For example, if you were to have an orange, and you painted it blue, it is still an orange, whereas if you burned the orange, it is no longer an orange. It would be soot/ash. 

Ithink is d. physical property