1.3 Volumetric Analysis

Question 1

Convert molL- to gL-

Answer 1

multiply by molar mass

x M

Question 2

Convert gL- to molL-

Answer 2

divide by molar mass

/ M

Question 3

Convert gL- to %wv

Answer 3

divide by 10

/10

Question 4

Convert %wv to gL-

Answer 4

multiply by 10

x 10

Question 5

Convert gL- to ppm (mgL-)

Answer 5

multiply by 1000

x 1000

Question 6

Convert ppm (mgL-) to gL-

Answer 6

divide by 1000

/ 1000

Question 7

ppm (mgL-) to ppb (ugL-)

Answer 7

multiply by 1000

x 1000

Question 8

ppb (ugL-) to ppm (mgL-)

Answer 8

divide by 1000

/ 1000

Question 9

%wv
%ww
%vv

Answer 9

wv - weight/volume
ww - weight/weight
vv - volume/volume

Question 10

How to complete stoicheometric calculations

Answer 10

1. Write balanced equation
2. Determine moles of known
3. Use mole ratio to determine moles of unknown
4. Calculate either mass or concentration of unknown

Question 11

Dilution factors

Answer 11

Remove a sample from a concentrated sample into deionised water a volume of deionised water.
volume of sample/final volume = dilation factor

Question 12

Limiting factor

Answer 12

The reactant the reacts to completion as it limits the reaction

Question 13

Steps to make standardised solution

Answer 13

1. weigh out appropriate amount of solid into a beaker
2. transfer compound into volumetric flask using clean dry funnel
3. throughly rinse beaker and funnel which contained the compound with deionised water and pour into volumetric flask
4. fill volumetric flask approximately halfway
5. shake with lid on until completely dissolved
6. fill to just below the calibration mark with deionised water
7. top up flask with deionised water using a teat pipette one drop at a time until the bottom of the meniscus lies on the calibration mark
8. replace lid and shake throughly