Volumetric Analysis Flashcards
Quantative
Find the amount of something
Qualilitve
Identify the presence of a particular substance
Solution
Completely perfect mixture of a solute and solvent
In a solution the solute particles are uniformly distributed throughout the solvent, solution is Homogeneous
Concentration
The amount of solute dissolved in a given volume of solvent
%w/w
G/100g
Divide both sides by no of grams of solution then x100
%w/v
G/100cm3
Divide both sides by the no of cm3 then x 100
%v/v
Cm3/100cm3
Divide both sides by total no of cm3 then x100
PPM
1ppm= 1mg/L
Divide by no of cm3 then x1000
Molarity
No of moles of solute per L of solution ie Mol/L
g/L
Mol/L x RMM
Standard solution
Solution whose concentration is accurately known
Primary standard
Substance that can be obtained in a stable pure and soluable solid
So that it can be weighed out and dissolved in water to give a solution of accurately known concentration
Give an example of a primary standard
Anhydrous Sodium carbonate
What are the criteria of a primary standard
Must be in a highly pure state
Must be stable in air
Must dissolve easily in water
High molecular mass
Rapid and complete reaction
Anhydrous
What is the primary standard used in acid base titration
Anhydrous sodium carbonate
What is a standardised solution
Obtained its concentration from titrations
Titration
An experiment where the measured volume of 1 solution is added to the known volume of another solution until the reaction is complete
What is a volumetric flask used for
Make up standard solutions
How do you fill a pipette
Using a pipette filler
Why is a pipette filler used
Safety
Where does the acid go
Burette
How to fill a pipette
Rinse with deionised water
Rinse pipette with what you are filling it with
Fill pipette using pipette filler until the bottom of the meniscus rests on the mark when measured at eye level
Place end of pipette into conical flask and drain
Wait 5 seconds and touched tip against the side of the conical flask
Do not blow out the last drop
Why do you not blow out the last drop when emptying a pipette
Drop is already taken into account in the calibration of the pipette. If You blow out last drop then you have more than 25cm and you have no idea how many moles you have transferred
How to fill a burette
Clamp burette vertically in retort stand
Lower burette over edge of bench and ensure tap is closedRinse burette with both deionised water and the acid and discard rinsing
Place funnel into burette and fill with acid above the 0 line
Remove funnel
Place waste beaker under tap and open tap to fill the space below the tap
Allow acid to flow out until the bottom of the meniscus rests on the 0 mark at eyelevel
