Answer : When a parallel circuit is built the voltage across each of the components remains the same, also the total current passed is the equal to sum of the currents passing through each components in the circuits.
When 2 or more components are tried to be connected in parallel they maintain the same potential difference (in voltage) across their ends of the circuit.
The potential differences across the components are the observed to be same in magnitude, and they have identical polarities between them.
Then, this same voltage is applicable to all circuit components connected in parallel.
So, if each bulb is wired to the battery in a separate loop, the bulbs will be in parallel series.
——>Ba+AlCl2
—->3Ba+2AlCl3 to balance the equation
since the unit for the heat of fusion is kJ/mol, you're going to have to convert the grams into moles in order to cancel out the unit. After that, you can solve like normal.