Give example of two substances that can undergo physical and chemical changes, depending upon the conditions

cbse
cbse-class-7-science
chemical-changes
physcial-and

#1

Give example of two substances that can undergo physical and chemical changes, depending upon the conditions.

Answer:

  1. On heating, wax melts (physical change) but on burning it forms carbon dioxide (chemical change).
  2. On heating, water converts to water vapours (physical change) but on passing
    electricity through it, it splits into hydrogen and oxygen (chemical change).