Answer:
Substances 1 and 2
Explanation:
an element only has 1 kind of atoms :3
CH4 + 2O2 → CO2 + 2H2O
there are four peaks in the 13c NMR (B)
CH4 + 4Cl2 --> CCl4 + 4HCl
Explanation: Message me if you need a thorough explanation
Chemical change :has change in mass, heat is needed, new element is formed, hard to reverse.......
Physicalchange:does not have change in mass, heat is not necessary, no new element is formed, easy to reverse
Physical properties.
