practical

Question 1

how do u make up a volumetric solution

Answer 1

• use a weighing bottle weigh and reweigh
• wash out weighing bottle
• do all washing
• add rest of distilled water with graduated pipette

Question 2

what could explain anomolous results of a titration

Answer 2

• overshoot end point
• didnt swirl fast enough
• didnt read from eye level meniscus
• didnt make sure no air bubble in the beurette

Question 3

how do u improve accuracy of a titration

Answer 3

include all washing
use dry mass bottle
decrease % uncertainty by using larger volumes

Question 4

what do u do to have a correct enthalpy change graph

Answer 4

extrapolate lines fron 0-3

and 5-10

Question 5

why do u extrapolate the line

Answer 5

to compensate for heat loss to surrounding due to fast exothermic reaction

Question 6

how do u measure rate of reaction change

Answer 6

choose 5 temps but dont go above 55 degrees

SODIUM THIOSULPHATE and HCL forms NACL SO2 S

Question 7

what covers the cross for the thipsulphate reaction

Answer 7

a solid sulphur precipitate

Question 8

how to carry out ethanal oxidation

Answer 8

-add conc sulphuric acid to water in pear shaped flask

DONT DO THE OTHER WAY ROUND

Question 9

imp bits for distillation

Answer 9

round bottomed flask

anti bumping granules

Question 10

describe reflux and key points

Answer 10

vapour of product condensed and returned to reaction
remains unsealed or pressure too high
pear shape for small volume round bottomed for large

Question 11

what are thiosulphate and iodine reaction with hydrogen peroxide

Answer 11

H2O2 + 2H+ 2I- —-> I2 and 2h20

2S2O2 + I2 —-> 2I- and S4O6 2-

Question 12

for measuring EMF

Answer 12

wash / sand electrode

degrease with propanone

Question 13

whats the rule with titrations

Answer 13

CALIBRATE PH PROBE

Question 14

how to do tlc separation of tablet

Answer 14

pestle and mortar to crush tablet
dissolve in ethanol
capillary tube
air dr