Question
Packing of $$N{a^ + }$$ and $$C{l^ - }\,ions$$ in sodium chloride is depicted by the given figure. Choose the correct option regarding formula mass of sodium chloride.
Packing of $$N{a^ + }$$ and $$C{l^ - }\,ions$$ in sodium chloride is depicted by the given figure. Choose the correct option regarding formula mass of sodium chloride.
A.
In the solid state, sodium chloride does not exist as a single entity.
B.
Formula mass of $$NaCl$$ is $$68.0\,u.$$
C.
Formula mass of $$NaCl$$ is the sum of atomic masses of $$Na$$ and $$Cl.$$
D.
Both (A) and (C).
Answer :
Both (A) and (C).
Solution :
Formula mass of $$NaCl=$$ Atomic mass of $$Na$$ + Atomic mass of $$Cl$$ $$ = 23.0\,u + 35.5\,u = 58.5\,u$$
Formula mass of $$NaCl=$$ Atomic mass of $$Na$$ + Atomic mass of $$Cl$$ $$ = 23.0\,u + 35.5\,u = 58.5\,u$$