What is the molar mass of lead (II) chloride (##PbCl_2##)?

##PbCl_2## has a molar mass of 278.1 g/mol

##color(grey)"We will use the formula below to answer the question:"##

atomic weight of element ##xx##number of atoms given by subscript ##=## molar mass

You should have a periodic table available so you can determine the atomic weight of Pb and Cl:

• Pb has an atomic weight of 207.2 g/mol
• Cl has an atomic weight of 35.45 g/mol

From the chemical formula, we have one Pb atom, so the would just be 207.2 g/mol

Next, you have two Cl atoms, so you would multiply the of Cl by 2 to obtain an atomic weight of 70.90 g/mol

Now you want to add the mass of each atom together to obtain the molar mass of the entire compound:

##color(violet) ("207.2 g/mol + 70.90 g/mol = 278.1 g/mol")##