Assertion: metal's electron | /r/CapableOf | fill shell
Facets:
value: progressively
type: MANNER
Source sentences:
text: As atomic number increases, electrons progressively fill these shells and subshells more or less according to the Madelung rule or energy ordering rule, as shown in the diagram.
text: Halogens (chlorine etc...) are reactive because they "want" an electron to fill their shell.