Question

Paper thickness varies. Typically, 100 sheets are about a cm thick. Atoms typically vary from 1 to 3 angstroms in radius. (An angstrom is 10-10 m.) Suppose a piece of paper is 0.0072 cm thick. How many atoms span the thickness if the radius of the atom is 1.23 angstroms

Answer 1

Answer:

$292683$

Explanation:

Thickness of a piece of paper = 0.0072 cm

Radius of an atom = $1.23\ \AA$

Conversion factor of $\AA$ to $\text{cm}$ is

$1\ \AA=1\times 10^{-10}\ \text{m}=1\times 10^{-8}\ \text{cm}$

Diameter of an atom = $2\times 1.23\times 10^{-8}=2.46\times 10^{-8}\ \text{cm}$

Number of atoms in one piece of paper is

$\dfrac{0.0072}{2.46\times 10^{-8}}=292682.92\approx 292683$

Hence, the number of atoms in one piece of paper is $292683$.