Halogens (atoms with 7 valence electrons) and Hydrogen
or generally, atoms with their shells almost full
Lar mass of Ca<span> = 40.08 </span>grams/mole 77.4 g Ca<span> * ( 1 </span>mole Ca<span>/ 40.08 ... n = m / M 1mol </span>Ca<span>weights 40 gmol-1 n = 77,4 / 40 = 1.93 </span>mol<span>.</span>
Answer:
26.981539 u
Atomic number: 13
Symbol: Al
Electron configuration: [Ne] 3s²3p¹
