chemical changes
100

what is a mixture that can be used as a chemical change

mix vinegar and baking soda for a bubbley explosion. 

200

what is it called when iron starts to rust and change colors?

oxidation

300

what/how do you know if something is changed chemically give at least two answers.

the smell the taste the color any of these are correct

400

 State whether the combination of hydrogen and oxygen to form water is a chemical or physical change.

if you know this its chemical change

500

what is the element with 173 neutrons

copernicium