Question

identify the chemical change:
melting of ice or conservation of milk into curd

Answer 1

Dear student.
Melting of ice is a physical change because it involves change only in the physical state of water, from ice in the solid state to water in the liquid state. Moreover, no new chemical substance is formed in the process and this change is reversible. Water can be converted back into ice simply by freezing. Hence melting of ice is a physical change.
Conversion of milk to curd is a chemical change as the reaction is irreversible and the curd formed once cannot be converted to milk again..
Regards