Question

The radius of a potassium atom is 231 pm. How many potassium atoms would have to be laid side by side to span a distance of 4.77 mm?

Answer 1

2.06×
`10^(10)` atoms

Step-by-step explanation:

The radius of potassium atoms= 231 pm

convert parts per million into m i.e, by multiplying by
`10^(-6)`

= 231×
`10^(-6)`

Potassium atoms would have to laid down at a distance apart= 4.77 mm

convert millimeter into meter i.e, by multiplying by
`10^(-6)`

= 4.77 ×
`10^(-6)`

Now, we have to find the number of potassium atoms,

Number of potassium atoms=
`(4.77 . 10^(-6) )/(231.10^(-6) )`

Number of potassium atoms=2.06×
`10^(10)`

Number of potassium atoms= 2.06×
`10^(10)` atoms

Hence, the correct answer is 2.06×
`10^(10)` atoms

Answer 2

To determine the number of potassium laid side by side by a given distance, we simply divide the total distance to the diameter of each atom. The diameter is twice the radius of the atom. We calculate as follows:

number of atoms = 4770 / 231x10^-12 = 2.06x10^13 atoms