How many liters of 0.4 M sodium hydroxide do you need in order to have 3.0 moles of water? 2NaCl(aq) + 2H20(l) 2Na0H(aq) + Cl2(g)

Question

I don't know what to do

Answer 1

You have the reaction written backwards, and also the moles of H2O produced from the reaction of NaOH + Cl2 gas will depend on the concentration of NaOH AND THE TEMPERATURE. So, the following are the possible reactions, and we can't really answer the question without knowing which is occurring.

2NaOH(aq) + Cl2(g) ==> NaCl(aq) + NaOCl(aq) + H2O(l) if NaOH is dilute and cold

6NaOH(aq) + 3Cl2(g) ==> 5NaCl(aq) + NaClO3(aq) + 3H2O(l)

If we assume that 0.4 M NaOH is dilute and the reaction is run under cold temperature conditions, then we proceed as follows:

NaOH(aq) + Cl2(g) ==> NaCl(aq) + NaOCl(aq) + H2O(l) ... balanced equation

3.0 moles H2O x 1 mole NaOH / mol H2O = 3.0 moles NaOH needed

Volume of NaOH needed:

(x L)(0.4 mol/L) = 3.0 moles

x = 7.5 liters of 0.4 M NaOH