Question

How many atoms of each type are in six formula units of $A{g_2}S{O_4}$?

Answer 1

To figure out how many atoms are in a formula unit, we must first understand what a formula unit is and how to figure out how many atoms are in a formula unit. We must count the number of atoms in a formula unit to find the number of that atom in that formula unit. "In an ionic composition, a formula unit denotes the lowest whole number ratio of ions." The formula's units are atoms of the element in concern, whereas the coefficients are moles.

Complete answer:
From the given formula we can see that there are $2$ atoms of silver ($Ag$) , $1$ atoms of sulphur ( $S$ ) and $4$ atoms of Oxygen ( $O$ ) .
It is given that there are $6$ units of $A{g_2}S{O_4}$ that is we have $6A{g_2}S{O_4}$
We know that the coefficient $6$ tells us that there are $6$ molecules of Silver Sulfate ($A{g_2}S{O_4}$)
So we must multiply the single molecule values by $6$ ,
Total atoms of silver $= 2 \times 6 = 12$
Total atoms of sulphur$= 1 \times 6 = 6$
Total atoms of Oxygen$= 4 \times 6 = 24$
Hence, the total number of atoms of silver are $12$ , total number of atoms of sulphur $6$ and total number of atoms of oxygen are $24$ .

Note:
The kinds and numbers of atoms in the smallest representative unit of a material are shown in a chemical formula. The formula unit is used in mineralogy because minerals are virtually exclusively ionic or network solids. The unit cell is defined by the number of formula units and the dimensions of the crystallographic axes.