Physical or chemical change

 

Hypothesis: There will be sparks, a heat output, and a physical reaction, which may turn yellow.

Equipment: Sample of ZnO (zinc oxide). Heat source - hot plate, scales, heatproof container - Evaporating dish, tongs, and heatproof mat.

Method: 

Get sample of ZnO in an evaporating dish

Weigh the ZnO & container and record weight

Heat container & ZnO on hot plate

Take off heat & put on heat proof mat

Let cool - observe

Reweigh

Conclusion:

It actually turned slightly yellow after being on the hot plate for a little while. There was a slight chemical change however the powder turned white again so it was a physical change. The weight was 37 at the start and was still 37 at the end. In conclusion it was a physical change because the powder went yellow then back to white with ease.