The number of transferred electrons to form the ionic bond in one formula unit of each compound is as below
NaCl = 1 electron
CaS = 2 electrons
BaO= 2 electrons
KBr=1 electrons
LIF = 1 electron
explanation
ionic bond is formed between a metal and a nonmetal . This bond is formed when electron are transferred between cation and anion. To know how many electrons transferred you look the oxidation state of the metal.
for example
in NaCl only one electrons is transferred since Na is in oxidation state of +1. Na donate the one electron to Cl to form an ionic bond. Ba is in oxidation state of 2+ and hence it donate the two electrons to O to form ionic bond.
Answer:
~Na+1 is already in the preferred form. Because of this, the second ionization energy of sodium is higher than normal. Mg+1 loses an electron to form s2 p6 .
1954 to 1960 is the time period he was a pastor/minister
