indicate whether or not each of the following elements can form ions, and if so, give the ion symbol or symbols
a/ silicon
b/ barium
c/ berylium
d/ krypton
e/lead
f/ selenium
a/ Yes. Si4+ (or less commonly Si2+ or Si-4)
b/ Yes. Ba2+
c/ Yes. Be2+
d/ Yes. Kr+ (or less commonly Kr2+)
e/ Yes. Pb2+ (or less commonly Pb4+)
f/ Yes. Se2- (or less commonly Se-4)
a/ Silicon (Si):
Silicon can form ions, but it is not commonly found as an ion in nature. The most common ion formed by silicon is the +4 ion, known as the silicate ion (Si4+).
b/ Barium (Ba):
Barium can form ions. It commonly forms a +2 ion, known as the barium ion (Ba2+).
c/ Beryllium (Be):
Beryllium can form ions. It commonly forms a +2 ion, known as the beryllium ion (Be2+).
d/ Krypton (Kr):
Krypton is a noble gas and generally does not form ions. Noble gases are stable and have a full outer electron shell.
e/ Lead (Pb):
Lead can form ions. It commonly forms two different ions: a +2 ion, known as the lead(II) ion or plumbous ion (Pb2+), and a +4 ion, known as the lead(IV) ion or plumbic ion (Pb4+).
f/ Selenium (Se):
Selenium can form ions. It commonly forms a -2 ion, known as the selenide ion (Se2-).