Find the Number of Neutrons Pb

Find the element ${\displaystyle \mathrm{Pb}}$ on the periodic table.

The atomic weight is a measurement of the total number of particles in an atom\'s nucleus including both protons and neutrons. So the first step is to locate the atomic mass on the periodic table, and round the value to the nearest whole number.

The mass number is the number of particles in an atom\'s nucleus. The nucleus is made up of protons and neutrons.

Find the element ${\displaystyle \mathrm{Pb}}$ on the periodic table.

To find the number of protons in ${\displaystyle \text{lead}}$, first locate the element on the periodic table. Next, find the atomic number which is located above the element\'s symbol. Since ${\displaystyle \text{lead}}$\'s atomic number is ${\displaystyle 82}$, ${\displaystyle \mathrm{Pb}}$ has ${\displaystyle 82}$ protons.

Fill in the known values where ${\displaystyle N}$ represents the number of neutrons.

Rewrite the equation as ${\displaystyle 82+N=207}$.