How many milliliters of 0.200 m naoh are required to completely neutralize 5.00 ml of 0.100 m h3po4?

Approx. #19*mL#. We know that

#"Concentration"="Amount of substance in moles"/"Volume of solution"#

#"Moles of HCl"##=##30.4xx10^-3cancelLxx0.152*mol*cancel(L^-1)##=##4.62xx10^-3*mol#.

We need an equivalent quantity of sodium hydroxide; #0.250*mol*L^-1# sodium hydroxide is available.

So, #(4.62xx10^-3*cancel(mol))/(0.250*cancel(mol)*cancel(L^-1))xx10^3*mL*cancel(L^-1##=##??mL#

What I should have done at the beginning is to write the stoichiometric equation:

#NaOH(aq) + HCl(aq) rarr H_2O(l) + NaCl(aq)#

Why should I write this first? Because it establishes the stoichiometry; the 1:1 molar equivalence. One equiv of sodium hydroxide reacts with one equiv hydrochloric acid. Thus if I know the quantity of acid, I also know the quantity of base. There will be reactions where a different stoichiometry pertains.

Hello Jana

The balanced chemical reaction for this neutralization reaction is:

3NaOH (aq) + H3PO4 (aq) → Na3PO4 (aq) + 3H2O (l)

We need to first determine the # of moles of H3PO4 from its volume and molarity.  Then convert it to moles of NaOH using stoichiometry.  Finally, use the calculated moles of NaOH and its molarity (0.100 M) to figure out the volume needed.

Convert volume of H3PO4 from mL to L.

50.0 mL x (1 L / 1000 mL) = 0.0500 L

Molarity = mol / L

mol = Molarity x L

= 0.125 mol/L x 0.0500 L = 0.00625 mol H3PO4

Moles of NaOH.....

0.00625 mol H3PO4 x (3 mol NaOH / 1 mol H3PO4) = 0.0188 mol NaOH (rounded to 3 significant figures)

Molarity = mol / L

L = mol / Molarity

= 0.0188 / 0.100 = 0.188 L

Volume in mL = 0.188 L x (1000 mL / 1 L) = 188 mL of NaOH required

Recommended textbook solutions

Clinical Reasoning Cases in Nursing

7th EditionJulie S Snyder, Mariann M Harding

2,512 solutions

The Human Body in Health and Disease

7th EditionGary A. Thibodeau, Kevin T. Patton

1,505 solutions

Pharmacology and the Nursing Process

7th EditionJulie S Snyder, Linda Lilley, Shelly Collins

382 solutions

Williams' Basic Nutrition and Diet Therapy

14th EditionNancy Peckenpaugh

369 solutions

Video Transcript

first we need to write a balanced chemical reaction. The reaction is three moles of sodium hydroxide reacting with one mole of phosphoric acid. So we'll start with the five million liters of phosphoric acid, Convert the mill leaders to leaders by dividing by 1000 and then convert the leaders to moles phosphoric acid by multiplying by its polarity. Once we have moles phosphoric acid we can then convert to mold sodium hydroxide. With the 123 relationships. Now knowing molds sodium hydroxide, we simply divide by the polarity of sodium hydroxide at 0.2 molar to get the leaders of sodium hydroxide that's required and then we'll convert it to milliliters by multiplying by 1000 and we get 7.5 mL. For the 2nd question. Typically just ask one question at a time. When you submit things for the second question we need to convert the hydroxide concentration into the hydro knee um concentration. The formula is this one right here, rearranging it, we get the hydro any um concentration equal to K. W. Which is 1.8 times 10 to the negative 14 divided by the hydroxide concentration. 1.8 times 10 to the negative two Giving us 1.2 times 10 to -12 as the hydro knee um concentration. This reaction is the weak acid ammonia with the strong, sorry the weak base ammonia with a strong acid hydro nian any time we have a strong acid such as hydro knee um reacting with a weak or a strong base. It's always product favored. So this reaction is product favored