How many electrons are transferred between the cation and anion to form the ionic bond in one formula unit of each compound? (1 electrons, 2 electrons, 3 electrons, 4 electrons) ? nacicasbaokbrlif

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.