# Question #178d9

##### 1 Answer

You'd need **0.24 L** of phosphoric acid solution to react with that much sodium hydroxide.

Start with the balanced chemical equation for this neutralization reaction

Notice that you have a **3 times more** moles of sodium hydroxide to completely neutralize the acid.

Since you know the molarities of the solutions, and the volume of the sodium hydroxide solution, you can determine how many moles of sodium hydroxide are added

You can now use the aforementioned mole ratio to see how many moles of acid would be neutralized by this many moles of sodium hydroxide

Now use the solution's molarity to determine the volume

Rounded to two sig figs, the number of sig figs given for 1.8 M and 3.8 M, the answer will be