Lab Practical 1-6

clairebear2018's version from 2018-02-27 07:25


Question Answer
lab safety ruleswear protective clothing, don't contaminate personal items, keep hands and lab bench clean, know where safety equipment is, be safe and courteous
scientific methodobservation, hypothesis, experimentation, conclusion
density mass/volume
molecular mass formulasum of the atomic masses of all atoms in the molecule
steps to using a colorimeter plug in colorimeter to vernier lab quest, turn on, 90 secs to warm, set to 635nm, fill cuvette with 3/4 deionized water, wipe finger prints, insert cuvette, unlined sides of cuvette line up with yellow arrow, hold cal button until light stops blinking, push mode and set to time based, set duration, set time for 10 seconds and press ok
standard curve exampleconcentration would be known value, absorbance is unknown valuev1m1=v2m2
recognize HCl/NaOH as a strong acid and know how it will dissociate in waterit completely dissociates
understand what will happen to the pH of an unbuffered solution with the addition of acid and/or baseit will change pH very rapidly
P1000accurate between 220uL and 1000uL, reads in milliliters instead of microliters. use blue tip
P200 accurate between 20uL and 200uL. use clear tip
P20 accurate between 2uL and 20uL, use clear tip, numbers are typically black black red, change in color indicates the position of the decimal point
how to use micropipettes -setting desired volumeturn centrally located rings clockwise to increase volume or counterclockwise to decrease volume
beer lambert lawthe linear relationship between absorbance and concentration of an absorbing species