Online practical 1- is blood real

what volume of liquid can a P10 pipette hold + tip colour

• 0.5-10ul

• white tip

what volume of liquid can a P50 pipette hold + tip colour

• 5-50ul

• yellow tip

what volume of liquid can a P200 pipette hold + tip colour

• 50-200ul

• yellow tip

what volume of liquid can a P1000 pipette hold + tip colour

• 100-1000ul

• blue tip

what happens when you forget to press pipette plunger to 2nd stop when expelling liquid

inaccurate pipetting (not enough liquid)

what happens when you press the pipette plunger to the 2nd stop before putting the tip on

inaccurate pipetting (too much liquid)

what happens when you hold the pipette horizontally/with the tip pointing up when theres some liquid in there

damage to the pipette

what happens when you release the plunger too quickly/unevenly when taking liquid in

creates air bubbles in the tip (not enough liquid)

what is spectrophotometry

• identifies compounds & their conc based on wavelengths of absorbed light

• more advanced colorimeter

what is the visible range of wavlengths

340-700nm

what light can molecules with conjugated bonds absorb + why

• UV & visible range

• double bonds can combine & electrons spread all over the atoms

• energy needed to promote outer electrons is lowered

5 conjugated molecules

• pigments

• vitamins

• nucleic acids

• proteins

• Hb

what does a spectrophotometer measure

amount of light absorbed by a sample at particular wavelengths of light

relationship between absorbance & conc of absorbing molecules

absorbance is proportional to the concentration of the absorbing molecules in solution

how to work out absorbance (beer-lambert)

how to work out dilution factor

• total volume/ initial volume of stock solution

• initial solute concentration/ final solute concentration after dilution