Standarization of a Sodium Hyrdoxide Solution

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SUMMARY

The discussion focuses on the standardization of a sodium hydroxide (NaOH) solution using potassium hydrogen phthalate (KHP) as a primary standard. The participants clarify that the amount of KHP used (0.5 g) should be accurately measured prior to titration, rather than calculated. The titration data provided indicates initial and final volumes of NaOH used across three trials, which are essential for determining the molarity of the NaOH solution. The key equations involved are c=n/v and c1v1=c2v2, which are critical for calculating concentration based on the titration results.

PREREQUISITES
  • Understanding of titration techniques
  • Familiarity with molarity calculations
  • Knowledge of potassium hydrogen phthalate (KHP) as a primary standard
  • Proficiency in using the equations c=n/v and c1v1=c2v2
NEXT STEPS
  • Learn how to accurately weigh and prepare potassium hydrogen phthalate (KHP) for titration
  • Study the process of calculating molarity from titration data
  • Explore the significance of primary standards in titration
  • Investigate common sources of error in titration experiments
USEFUL FOR

Chemistry students, laboratory technicians, and educators involved in analytical chemistry and titration methodologies will benefit from this discussion.

Erayes
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Homework Statement


Hello, I missed a lab before the break because I was really sick and I need help. I was given the data from my partners for the titration lab and I don't understand how to calculate the amount of potassium hydrogen phthalate used in each trial, amount concentration of the sodium hydroxide solution and the average concentration of the solution. Thanks in advance.
They used .5g of KHP.

Trials(mL)
1 2 3
Initial volume of NaOH: 0 | 5.8 | 12.2 |

Final volume of NaOH: 5.8 | 12.2 | 17.3 |
Total Volume: 5.8 | 6.4 | 5.1 |

Homework Equations


c=n/v, n=m/mm c1v1=c2v2

The Attempt at a Solution


When they say amount do they mean g or moles?
n=m/mm
n=.5/204.22
n=0.002448
Do I use the final volumes to calculate amount concentration?
 
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Erayes said:

Homework Statement


Hello, I missed a lab before the break because I was really sick and I need help. I was given the data from my partners for the titration lab and I don't understand how to calculate the amount of potassium hydrogen phthalate used in each trial, amount concentration of the sodium hydroxide solution and the average concentration of the solution. Thanks in advance.
They used .5g of KHP.

Trials(mL)
1 2 3
Initial volume of NaOH: 0 | 5.8 | 12.2 |

Final volume of NaOH: 5.8 | 12.2 | 17.3 |
Total Volume: 5.8 | 6.4 | 5.1 |

Homework Equations


c=n/v, n=m/mm c1v1=c2v2

The Attempt at a Solution


When they say amount do they mean g or moles?
n=m/mm
n=.5/204.22
n=0.002448
Do I use the final volumes to calculate amount concentration?

Nobody can answer that nor should try because it is far too vague and unclear.
"They used 0.5 g of KHP". To do what?
OK it looks like like they used 3 volumes of the NaOH solution to titrate each time the same unstated volume of a KHP solution that was made up in unstated way from 0.5 g. KHP.
That's what you use KHP for, because you can do it precisely ("primary standard") as your book or manual certainly explains (though that precision is rather wasted given your colleagues' poor reproducibility!)
From the titrations you can deduce, within the said loose limits of their precision, the molarity of the NaOH.
That is very likely the object lf the experiment so you are asking the wrong question to the wrong people - your colleagues should tell you what they did with the KHP.
 
Erayes said:
I don't understand how to calculate the amount of potassium hydrogen phthalate used

It is not something you should calculate - it is something that should be measured (and precisely!) before the titration. As epenguin signaled, KHP is one of these substances that can be prepared very pure and weighed very accurately.
 

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