A student observes actions that occurred in four different eggs. Which action describes only a chemical change?

A. a cut up egg

B. a stirred egg

C. a rotting egg

D. a dropped egg

C. a rotting egg

Explanation:

Chemical change:

The changes, that occur due to change in the composition of a substance and result in a different compound is known as chemical change.

These changes are irreversible

These changes occur due to chemical reactions

These may not be observed with naked eye

Example:

Combustion of fuel or wood: that oil or wood convert into energy, CO2 and ash in case of wood

Boiling of egg or rotten egg: that change the chemical composition of protein in the egg. So it is considered as chemical change while others cut up egg, stirred egg and dropped egg are just involve the changed in state of egg no chemical reaction occur.

Physical Change

The changes that occur only due to change in shape or physical properties but their chemical or internal composition remain unchanged.

These changes were reversible.

They have same chemical property.

These changes can be observed with naked eye.

Example:

Water converting to Ice

Water converting to gas