Answer: The molecular formula will be 
Explanation:
Molecular formula is the chemical formula which depicts the actual number of atoms of each element present in the compound.
Empirical formula is the simplest chemical formula which depicts the whole number of atoms of each element present in the compound.
The empirical formula is 
The empirical weight of
= 1(12)+3(1)= 15g.
The molecular weight = 45.0 g/mole
Now we have to calculate the molecular formula:

The molecular formula will be=
Thus molecular formula will be 
Answer:
The molarity is: 1 M
Explanation:
We define molarity as an amount of moles in 1000ml of solution (1 liter)
500ml---------0,5 moles AlCl3
1000ml------x= (1000ml x 0,5 moles AlCl3)/500ml = 1 moles ACl3--> 1 M