Hannah does an experiment. she has two colorless chemicals that she mixes together in a beaker. which of the following indicates that a chemical change occurs when she mixes the two chemicals together?
i. the chemicals change color from colorless to purple.
ii. a yellow gas forms.
iii. a brown solid forms in the bottom of the beaker.
iv. the temperature of the chemicals rises 15°c.
a.
ii and iii only
b.
i and iii only
c.
i, ii, iii, and iv
d.
i, ii, and iii only