Which action forms a different chemical substance?
1 2 3 4
crushing a rock burning a piece of wood mixing salt and pepper melting an ice cube
Question: Which action forms a different chemical substance?
(1) crushing a rock
(2) burning a piece of wood
(3) mixing salt and pepper
(4) melting an ice cube

Answer: (2) burning a piece of wood
Answer: (4) melting an ice cube
Question: Which action forms a different chemical substance?
(1) crushing a rock
(2) burning a piece of wood
(3) mixing salt and pepper
(4) melting an ice cube
Answer: (2) burning a piece of wood