<span>Helium = 1
Carbon = 8
Nitrogen = 8
Strontium = 52
Tellurium = 71
If you look on a periodic table, on each element there is a number on
the top left. This represents the number of protons in an atom. Protons
have a mass of 1 (in relative to Carbon-13)
If we take nitrogen-15 for example; The number 15 tells you that the
isotope has a mass of 15. Now if you look on the periodic table,
Nitrogen has a proton number of 7. Only protons and neutrons have a
mass, electrons are considered to be negligable. Therefore the number of
neutrons Nitrogen-15 contains is 15 - 7 = 8 </span>
A) a column
example: earth alkaline metals
Answer:
3.6 times 10^4
Explanation:
Scientific notation is between 1-9. So, we move 36000 to 4 decimal places. SO it would be 3.6 times 10^4. Scientific Notation always has the base of 10 . Enjoy :)
The word elliptical refers to an Oval.
Answer:
C
Explanation:
u can't touch a chemical with bare skin