During the Physical changes
Yes if you add an energy to an electron the electron will become excited, and it will jump to its highest level then go back down releasing energy
These rocks were either roasted or exposed to severe weathering
Answer:
First choice: 2
Explanation:
There are 2 phosphorous (P) in the substance.
Ignore the strontium (Sr3) part because you are looking to isolate the P from (PO4)2.
Break the chemical equation apart to get 1 Phosphorous atom, and 4 Oxygen atoms.
Now, multiple 1 by 2 because that are 2 phosphate to get 2 phosphorous atoms.
