Answer:
1st one is...
Explanation:
The 1st one is change in size or shape. 2nd one is formation of precipitate. 3rd one is physical change. 4th one is formation of gas.
The products enable our nations efforts to improve energy efficiency . From insulation to coolants to packaging , the product of chemistry help save energy day . But chemistry also is the source of many innovative technologies that drive cleaner energy options , create green jobs and propel u.s. economic growth.
It can be a compound or a single element. An element is a pure substance that cannot be separated into simpler substances by chemical or physical means. There are about 117 elements, butcarbon, hydrogen, nitrogen and oxygen are only a few that make up the largest portion of Earth.
I would say d.
The answer is c because the calculations for the elements have to connect with the compounds
