Answer:
Explanation:
1 ) Under the proper conditions, water will break apart into hydrogen and oxygen gas.
When water is converted into hydrogen and oxygen , this change is irreversible under ordinary condition . It can not be possible by easy means to obtain water again from hydrogen and oxygen . Hence this is chemical change .
2 )
Water will dissolve sodium chloride, or table salt.
When sodium chloride or table salt is dissolved in water , we can easily get back salt by boiling the water off . The residue will be salt . Hence is is reversible change . Hence this represents physical change.
3 )
Formation of bead on waxy surface is not something in which any change is taking place . Bead too is a water . So it is a physical change .
4 )
When ice melts to form water , it is physical change because , we can get back ice from water easily by putting water in freeze. Hence it is a physical change.
