Question #efddd

1 Answer
Apr 22, 2015

You need 21.8 mL of your sulfuric acid solution to neutralize that much sodium hydroxide.

Start with the balanced chemical equation for this neutralization reaction

H_2SO_(4(aq)) + color(red)(2)NaOH_((aq)) -> Na_2SO_(4(Aq)) + 2H_2O_((l))H2SO4(aq)+2NaOH(aq)Na2SO4(Aq)+2H2O(l)

Notice that you have a 1:color(red)(2)1:2 mole ratio between sulfuric acid and sodium hydroxide. This means that you need 2 moles of the lattter for every 1 mole of the former in order for complete neutralization to take place.

If you have less than 1 mole of sulfuric acid for every 2 moles of sodium hydroxide, you won't get complete neutralization, i.e. you'll have base remaining in solution.

Use sodium hydroxide's molar mass to determine how many moles of NaOHNaOH must be neutralized

0.220cancel("g") * "1 mole NaOH"/(39.997cancel("g")) = "0.00550 moles NaOH"

This means that you'd need

0.00550cancel("moles NaOH") * ("1 mole "H_2SO_4)/(color(red)(2)cancel("moles NaOH")) = "0.00275 moles" H_2SO_4

Since you're dealing with a sulfuric acid solution, you can use its molarity to determine what volume would contain this many moles

C = n/V => V = n/C

V = (0.00275cancel("moles"))/(0.126cancel("moles")/"L") = "0.02183 L"

Expressed in mL and rounded to three sig figs, the answer will be

V = color(green)("21.8 mL")