Composition of a Mixture by Acid-Base Titration

In summary, the conversation discusses a problem involving a solid sample containing a mixture of table salt and citric acid, which is dissolved in water and then titrated with NaOH solution to reach an endpoint. The goal is to calculate the mass percent of citric acid in the solid mixture, but the process and equations involved are not fully explained.
  • #1
veena
7
0
A 1.00-g solid sample containing a mixture of table salt (NaCl) and citric acid (H3C6H5O7, a triprotic acid) is dissolved in 15 mL of water.
Titration of the acid solution requires 40.00 mL of 0.2003 M NaOH solution to reach the endpoint.
Calculate the mass percent H3C6H5O7 in the solid mixture.


Can somone please explain how to do this problem...??
 
Physics news on Phys.org
  • #2
Start by writing out the neutralization equation.
 
  • #3
I have tried but i don't know how to solve for M2

M1 x V1 = M2 x V2

can u help please
 
  • #4
Start by writing out the neutralization equation.
 
  • #5
First, figure out how many moles of NaOH were used, this will be equivalent to the amount of [tex]OH^{-}[/tex] in the titration mixture, if its the end point [tex]OH^{-} = H^{+}[/tex], I hope that gets you closer to your final goal, as its bad policy for us to just give you a full answer.

Or, just do what chem said, write the neutralization equation (I do the more manual way personally ¬_¬ )
 
  • #6
veena said:
A 1.00-g solid sample containing a mixture of table salt (NaCl) and citric acid (H3C6H5O7, a triprotic acid) is dissolved in 15 mL of water.
Titration of the acid solution requires 40.00 mL of 0.2003 M NaOH solution to reach the endpoint.
Calculate the mass percent H3C6H5O7 in the solid mixture.


Can somone please explain how to do this problem...??
"triprotic acid"... Which endpoint? Is your course "elementary chemistry" or is it undergraduate "Quantitative Chemistry"?
 
  • #7
I think he will be reffering to the third endpoint, rather than the first.
 

What is the purpose of an acid-base titration?

The purpose of an acid-base titration is to determine the concentration of an unknown acid or base in a solution by using a known concentration of acid or base. This is done by adding the known solution to the unknown solution until the reaction is complete, and the concentration can be calculated using the volume and concentration of the known solution.

What equipment is needed for an acid-base titration?

The equipment needed for an acid-base titration includes a burette, a flask or beaker, a pipette, an indicator, and a stirrer. The burette is used to measure and add the known solution, while the flask or beaker is used to hold the unknown solution. The pipette is used to accurately measure the volume of the unknown solution, and the indicator is used to determine when the reaction is complete. The stirrer is used to mix the solutions together.

How is the endpoint of an acid-base titration determined?

The endpoint of an acid-base titration is determined by using an indicator, which is a substance that changes color when the reaction is complete. The indicator is added to the unknown solution and as the known solution is added, the color of the solution will change. The endpoint is reached when the color of the solution changes permanently, indicating that the reaction is complete.

What is the difference between a strong acid and a weak acid in an acid-base titration?

A strong acid is completely ionized in water and will have a higher concentration of hydrogen ions, while a weak acid is only partially ionized and will have a lower concentration of hydrogen ions. This means that a strong acid will require less volume of the known base to reach the endpoint of the titration compared to a weak acid.

How can errors be minimized in an acid-base titration?

Errors in an acid-base titration can be minimized by ensuring accurate measurements of the solutions, using the correct equipment, and performing multiple trials to calculate an average. The endpoint can also be determined more accurately by using a pH meter instead of an indicator. Additionally, proper technique and careful observation can help minimize errors in the titration process.

Similar threads

  • Biology and Chemistry Homework Help
Replies
2
Views
1K
  • Biology and Chemistry Homework Help
Replies
5
Views
2K
  • Biology and Chemistry Homework Help
Replies
16
Views
3K
  • Biology and Chemistry Homework Help
Replies
2
Views
3K
  • Biology and Chemistry Homework Help
Replies
1
Views
2K
  • Biology and Chemistry Homework Help
Replies
2
Views
21K
  • Biology and Chemistry Homework Help
Replies
6
Views
12K
  • Biology and Chemistry Homework Help
Replies
3
Views
2K
  • Biology and Chemistry Homework Help
Replies
4
Views
3K
  • Biology and Chemistry Homework Help
Replies
5
Views
4K
Back
Top