15.9994 amu
15.9994
Devide mass by atomic mass to get 15 atoms Ne 300 (amu) / 20.2 (amu/atom Ne) = (14.9 atoms) = 15 atoms (= 303 amu)
15
The element with the atomic number 15 is Phosphorus.
Write "9" then the forward slash "/" and then "15". Or you can write the 9 above a horizontal line with the 15 below that line.
You write it as 3/15. However, that can be simplified to 1/5.
you do 15 * 15 * 15
15 = quinze
15%
It would have 7 protons It woul have 7 electrons
15/100 = 0.15 = 15%
4/15