Chemistry.

posted by .

hi again, thanks to the previous help i got the first part of the question. the second part builds on the first part as we used that stock solution for titration of the next. we are now given:

Concentration of Standard Acid Soultion (M) = 0.100 M

Volume of Standard Acid Solution (mL) = 25.00 mL

Volume oof Stock Solution of NaOH (mL) = 18.65 Ml

Concentration of Stock Solution of NaOH (M) = 0.108 M (from previous question asked)

Now it is asking for the concentration of the stock solution.

Would you just do this:

0.100M X 0.025 L = ?? mols

and then ?? mols / 18.65 mL?

is that how to do it or is there more processes involved?

  • Chemistry. -

    You're on the right track and you ALMOST have it.

    Would you just do this:

    0.100M X 0.025 L = ?? mols
    exactly right.

    and then ?? mols / 18.65 mL?
    remember definition of M = mols/Liter. Therefore, you must change 18.65 mL to liters. Otherwise, you have it down ok but see the note in italics that follows.
    Technically you can't work the problem nor solve for the molarity of the solution without an equation. You may have one that was given to you and you just didn't copy it into this post. If you know what the acid is (HCl for example and I think that was the previous post) then you can write it
    NaOH + HCl ==> NaCl + H2O.
    The idea here, and what I'm cautioning you against, is that we assumed above that the mols of the acid and the mols of the base were the same and that works as long as the mole ratio in the equation is 1:1 as it is for HCl and NaOH. BUT, if you have an equation in which the ratio is NOT 1:1, for example,
    H2SO4 + 2NaOH ==> Na2SO4 + 2H2O THEN
    you must convert using the equation from mols of one reactant to mols of the other. In this case you were given standard acid of 0.100 M. Let's supposer that was H2SO4 and you have the equation I wrote above. Then 0.100 x 0.025 L = 0.0025 mols H2SO4.
    Then 0.0025 mols H2SO4 x (2 mol NaOH/1 molH2SO4) = 0.0050 mols NaOH.
    Then M NaOH = mol NaOH/L = 0.0050 mols/0.01865 L = ??molarity NaOH.

  • Chemistry. -

    that did make sense, and my little mistake was the conversion from mL to L. i referenced into some of my material and i believe the standard acid is probably H2SO4 so i will try it out and see my result.

    sorry to keep bugging you, but if it makes you feel better i am understanding it more.

    what if you have the same numbers, but you are trying to find the concentration of an UNKNOWN acid. all you have is:

    Volume of Unknown Acid
    Volume of Stock Solution
    Concentration of Stock solution..

    how would you determine that? same process?

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. Math

    3(-5)squared -2/-5(2)/2 squared I don't get the second part but... any number squared is positive so 3(-5) squared is 3x25 if only (-5) is squared. If the whole thing is squared then multiply first, (3x-5) then squared the answer. …
  2. Physics

    An automobile tire has a radius of 0.380 m, and its center moves forward with a linear speed of v = 19.0 m/s. (a) Determine the angular speed of the wheel. (Assume that there is no slipping of the surfaces in contact during the rolling …
  3. college: Chemistry

    Hi there I need help with my chemistry homework There are two parts to the first question and i did the first part and i got E= -6.54E-18J. Part A) Calculate the energy (in J) of the photon associated with the transition of electron …
  4. Chemistry

    Part 1: Each molecule of NO2, nitrogen dioxide, consists of 1 atom of N and 2 atoms of O. If you have 0.155 g. of NO2, how many molecules of NO2 do you have ?
  5. Chemistry

    If your solution’s final volume of 32.55 mL yields 3.6 grams of AgCl, determine the Molarity of the final solution. Also, how many milliliters of a 1.85 M solution of AgNO3 did you add to an excess of aqueous NaCl to provide the …
  6. algebra

    On the second part of her trip, Tamiko drove 21 miles less than two times as far as the first part. Let f represent the number of miles driven on the first part of her trip.Then write an algebraic expression that represents the number …
  7. Maths

    Divide Rs 116 among 4 parts such that 5 added to first part 4 subtracted from the second part 3 mutltiplied by third part and fourth part divided by 2 are all equal
  8. Algebra help please

    Part A: Divide (16x^5y^4 + 6x^3y - 2x^2y - 24x^2y^4) by -2x^2y. Part B: How would your answer in Part A be affected if the x2 variable in the denominator was just an x?
  9. Algebra

    On the first part of a trip to Carmel traveling on the​ freeway, Marge averaged 70 mph. On the rest of the​ trip, which was 25 mi longer than the first​ part, she averaged 60mph. Find the total distance to Carmel if the second …
  10. math

    find the next number in the following sequence; 1/2,2/3,3/5,5/8, _ *please i need your assistance guys for this question* My idea is as follows denominator part for the given fraction =1+2 =3 then 2+3 =5, 3+5=8,therefore the next denominator …

More Similar Questions