Question

How many moles of chlorine gas are needed to make 3.6 moles of sodium chloride?Given the reaction: 2Na + Cl2 -> 2NaCl

Answer 1

The question requires us to calculate the amount, in moles, of chlorine gas (Cl2) necessary to obtain 3.6 moles of NaCl, and it gives the balanced reaction.

The first step in this kind of questions is to confirm if the reaction is balanced. Considering the reaction given:

2Na + Cl2 ---> 2NaCl

Since we have the same amount of Cl and Na on both sides of the equation, we can move on to the calculations.

From the stoichiometric coefficients of the reaction given, we can say that we need 1 mol of chlorine gas to produce 2 moles of sodium chloride. With that information, we can write:

1 mol Cl2 --------------- 2 mol NaCl

x --------------- 3.6 mol NaCl

Then, solving for x:

`x=\frac{3.6\text{ mol NaCl}*1molCl_2}{2\text{ mol NaCl}}\rightarrow x=1.8molCl_2`

Therefore, 1.8 moles of chlorine gas are necessary to produce 3.6 moles of NaCl (option A).