The first step we have to follow is to find the molar mass of FeCl2 using the atomic masses of each element:
![\begin{gathered} Fe=55.845g/mol \\ Cl=35.45g/mol*2=70.9g/mol \\ FeCl_2=126.745g/mol \end{gathered}](https://img.qammunity.org/2023/formulas/chemistry/high-school/t0q8eodxoukq3blhidduckrivoz264f82c.png)
It means that each mole of FeCl2 has a mass of 126.745g/mol.
Use the molar mass to find the mass of the given amount of moles:
![869molFeCl_2\cdot(126.745gFeCl_2)/(1molFeCl_2)=110,141.405gFeCl_2](https://img.qammunity.org/2023/formulas/chemistry/high-school/kioz1hth6900n7fiteb0qzgnhudssgv8e9.png)
It means that there are 110,141.405 grams of FeCl2.
In scientific notation it would be 1.10x10^5g.