Question

4. Name two materials which are smooth to touch.
5. Define opaque objects.
6. Name two substances which are not soluble in
water.
7. Name any one material which is smooth but
hard.​

Answer 1

Answer:

5) opaque objects are objects which do not allow light to pass

eg wood

6) sugar and salt are the objects which are not soluble in water

7) Diamond is the material which is smooth but hard

Explanation:

please mark this answer as brainlist

Answer 2

Explanation:

5) An opaque object is neither transparent ( allowing all light to pass through) nor translucent (allowing. some light to pass through) .

When light stikes an interface between two substances.

6) sand and flour

7) Diamond