Answer:
A pure substance consisting only of atoms with the same number of protons in their nuclei-these appear on the periodic table
Oxygen
Hydrogen
Carbon
Sulfur
Phosphate
Nitrogen
Magnesium
Calcium
Potassium
Chlorine
(I know that these are more examples than needed, but you can use any)
Answer: Really
Explanation:
Just look it up for this page and maybe you will find an anwser sheet.