Question

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? 1.the chemical change color from colorless to purple 2. A yellow gas forms 3.a brown solid forms in the bottom of the beaker 4.the temperature of the chemicals rises 15 celceus

Answer 1

I don't have too much faith in myself for this one xD. I can tell you this isn't a physical change (changing shape or form.) so exclude 3 and 4. So now they are out of the way, it's either 1 or two.

As far as I know, the answer is 2. A yellow gas forms.

But I cannot guarantee it's %100.

Answer 2

It's actually all of them