Lab Final Flashcards
Write Solubility Rules table
What are strong electrolytes?
Strong acid, strong base, salt (ionic compound)
What are weak electrolytes?
Weak acid, weak base
What are non-electrolytes?
Molecular and Organic compounds
Basic Anion
Any anion that reacts with water to produce hydroxide ions in solution
What are some examples of basic anions?
Carbonate, phosphate, sulfate, acetate, cyanide and fluoride
Where do basic anions come from?
Weak acids, because basic anions are the conjugate bases of weak acids
Potassium Hydrogen
KHP
What makes an effective buffer?
Concentrated enough to resist pH change
Ratio of conjugate acid and conjugate base is close to one
Why is it important to not have any bubbles in the tip of the buret?
Volume measurement will be inaccurate and actual titrant volume will be lower than measured volume
Percent Error
absolute value of (experimental minus actual divided by actual) x 100
What is precision and the precision standard for titrations?
The ability to reproduce the experiment so that the data obtained are close to one another
4 ppt
Will added KHP to flask w/60ml instead of 50ml of water affect the molarity of NaOH?
Unaffected
How will a buret wet w/water when you add NaOH affect the molarity of NaOH?
Too low
When KHP is wet when weighed how will this affect the molarity of NaOH?
Too high
When you titrate past the equivalence point by 0.50 ml how will this affect the molarity of NaOH?
Too high
Does the E-flask need to be dry?
No, because any water within the flask won’t have a direct effect on the number of moles in the solution
Does pipet need to be dry?
No, pipet will be conditioned with saturated Ca(OH)2 solution.
Common Ion Effect
presence of common ion decreases solubility of solids in solution
KSP: Buret was not conditioned
Too high
KSP: Ca(OH)2 solid in solution
Too high
KSP: Measured 24mL instead of 25mL
Too high
KSP: [HCl] was lower than bottle
Too high
