a.Write the electron dot structure for the atoms of sodium and chlorine.
b. What type of bond is formed between sodium and chlorine atoms?
c. Show the formation of sodium chloride with the help of electron dot structure.
d. Why do ionic compounds not conduct electricity in the solid state? In which state the conduction of electricity possible and why?
a.
The reactivity of the elements is determined by the tendency to have a completely filled valence shell. The electron dot structure of Na (sodium) and Cl (chlorine) atoms are shown in the figure below.
b.
To attain completely filled valence shell, Na has to lose the outermost electron, and Cl needs one electron to complete the valence shell.
By losing an electron, Na becomes Na+ (cation) and this electron is accepted by Cl to form Cl- (anion). The oppositely charged ions attract each other and form NaCl. They are held together by strong electrostatic forces of attraction. The bond existing between them is called an ionic bond.
c.
Figure 1: Formation of sodium chloride
d.
Ions in an ionic lattice are fixed at their positions and can only oscillate about their mean positions. Hence, in the solid state, the ions are not free to move. While in molten form, these ions can freely move in the solution which also allows the passage of electricity. The right reason is the absence of mobile ions in the solid state.
Ionic compounds conduct electricity in molten state because in these compounds ions are free to move and in molten state they contain cations and anions and hence are to conduct electricity.
Regards.
