Question

in the following reaction, what is the correct coefficient for aluminum chloride? al(s) + cl2(g) → alcl3(s) a) 4 b) 1 c) 2 d) 3

Explanation:

Step1: Balance the chemical equation

The un - balanced equation is $Al(s)+Cl_2(g)
ightarrow AlCl_3(s)$. To balance the chlorine atoms, we note that there are 2 chlorine atoms in $Cl_2$ and 3 chlorine atoms in $AlCl_3$. The least - common multiple of 2 and 3 is 6. So we put a 3 in front of $Cl_2$ and a 2 in front of $AlCl_3$: $Al(s)+3Cl_2(g)
ightarrow 2AlCl_3(s)$. Then we balance the aluminum atoms by putting a 2 in front of $Al$: $2Al(s)+3Cl_2(g)
ightarrow 2AlCl_3(s)$.

Answer:

C. 2