See explanations below.
Explanation:
growth of seed into seedling
- chemical (bio-chemical) change. The seed will never be there in its form again, the properties of the growth are different from the seed.
wax melting
- physical change. When heat is withdrawn, it reverts to the same solid wax, with only different physical properties (such as shape or texture).
making caramel
- chemical change. it is almost like burning part of the sugar content. The browning cannot be changed back to white sugar, smells and tastes different. However, on part of the sugar has undergone chemical change.
Tarnishing of silver
- chemical change. The brown substance is silver sulphide due to reaction of silver with sulphur dioxide present in minute quantities in the air. The silver can be made to shine again by REMOVING the silver sulphide, not by reversing the change.
grinding wheat to make flour.
- physical change. The compound is still flour that contains mainly starch. The chemical properties are the same as wheat, in providing nutrients, etc.
Adding copper and gold to make jewelry.
- physical change. The two metals together make an allow, which is basically a mixture. Both physical and chemical properties of the individual metals remain.
