<span>Its b.aluminum
I hope this helps and sorry if I am wrong </span>
You put in a variable to substitute the unknown number.
——>Ba+AlCl2
—->3Ba+2AlCl3 to balance the equation
<span>Avogadro's number
represents the number of units in one mole of any substance. This has the value
of 6.022 x 10^23 units / mole. This number can be used to convert the number of
atoms or molecules into number of moles. We do as follows:
4.50 mol Fe ( 6.022x10^23 atoms / 1 mol Fe ) = 2.71x10^24 atoms Fe present </span>