Question

Which of the following is a chemical change

(a) Rusting of metal               
(b) Moulding of metal      
(c) Alloying of metal​

Answer 1

rusting of metal is the answer

Answer 2

Answer:

a) cannot be because we can clean rust of metal using sand paper

b) true

c) alloying of metal is a physical change that can be undone using chemical processes