Identify each of the following as a physical or chemical change

Question

Identify each of the following as a physical or chemical change

a. a plant grows a new leaf.

b. chocolate is melted for a dessert.

c. wood is chopped for the the fireplace.

d. wood burns in a woodstove

Answer 1

a) mostly chemical, though in a way it's both.  A lot of chemical changes are involved in growing a new leaf, but there are physical changes too.

 

b) physical -- there's no chemical change when a substance changes state (e.g., solid to liquid)

 

c) physical

 

d) chemical -- anything burning usually involves a chemical reaction of adding oxygen and ending up with waste products and energy