chemistry

posted by .

A titration was performed on 50.0 ml of .250 M NaOH. After the addition of 71.4 ml of HCl,the phenolphthalein indicator changed from pink to colorless. What was the concentration of the HCl? im not sure how to figure this one out but here goes
200*.250*1000=50000
1000*121.4=121400
50000/121400=.412?
that was my best shot

I don't know what you did and since you didn't explain the steps you took OR use any units, I'm clueless.
Here is how you do it.
mols NaOH = mols HCl
M x mL = M x mL
0.250 M x 50 mL = M x 71.4 mL
Solve for M HCl.

Im sorry, that was very stupid of me for not explaining anything. Is this right?
0.250 M x 50 mL= 12.5ml
12.5 M x 71.4ml= 893


no if I solve for m I would have to

0.250 M x 50 mL = M x 71.4 mL
.250M*50=12.5ml
12.5ml=M*71.4
12.5ml=71.4M
12.5/71.4=.175ml

right number, wrong unit.
You are solving for M so M = 0.175M

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. Chemistry - Acid Base Titration

    When you complete a acid base titration of NaOH and HCl and how to you find the molarity/concentration of HCl. I used 9 mL of HCl with 50 mL of water. But when solving for concentration, do I use 9 mL or 59 mL (water + HCl)?
  2. ap chemistry

    please explain titration problems. I'm a total noob at this and am trying to answer some prelab questions. Examples: 1. How many mL of a 0.800 M NaOH solution is needed to just neutralize 40 mL of a 0.600 M HCl solution?
  3. Chemistry

    Hello, I need help with calculations for lab. I prepared excess NaOH and HCL solutions (unknown conc., ~0.1M). Then I standardized my NaOH solution by titrating known amounts of KHP (Potassium hydrogen phthalate)with it in the presence …
  4. Chemistry -help

    To determine the sodium carbonate content & total alkali in NaOH, the following steps were performed:- 1) 2.0g of NaOH was dissolved in 80ml of CO2 free water. 2) 3 drops of phenolphthalein indicator were added and the solution was …
  5. Chemisty

    The flask shown here contains 10.0 mL of HCl and a few drops of phenolphthalein indicator. The buret contains 0.270 M NaOH. What volume of NaOH is needed to reach the end point of the titration?
  6. Chemisty

    The flask shown here contains 10.0 mL of HCl and a few drops of phenolphthalein indicator. The buret contains 0.270 M NaOH. What volume of NaOH is needed to reach the end point of the titration?
  7. Chemisty

    The flask shown here contains 10.0 mL of HCl and a few drops of phenolphthalein indicator. The buret contains 0.270 M NaOH. What volume of NaOH is needed to reach the end point of the titration?
  8. Chemistry

    The flask here contains 10.0 mL of HCl and a few drops of phenolphthalein indicator. The buret contains .270 M NaOH. What volume of NaOH is needed to reach the end point of titration?
  9. Chemistry

    A student was given 100mL of HCL solution in a 250mL beaker and told that the HCL was 0.11M. The student was also given phenolphthalein indicator and 250 ML of 0.1234 M NaOH. The student first filled a buret with NaOH solution. The …
  10. chemistry

    A student prepares a solution of hydrochloric acid that is approximately 0.1 M and wanted to determine its precise concentration. A 25.00 mL portion of the HCl solution is transferred to a flask, and after a few drops of indicator …

More Similar Questions