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Predictions for Chemistry 2014 HSC? (4 Viewers)

emilios

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Anything that hasn't yet been asked? I'm feeling a couple of those obscure pracs that no one ever does coming up.
 
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For the long response, i reckon probably something to do with ethylene or a biopolymer.

Hopefully the test is straightforward.
 

photastic

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Combine Haber's impact of his time and today's actions when dealing with chemistry in the environment/society.
 

emilios

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i'll predict a lot of esters questions or those pracs in eutrophication/water quality questions
idk refluxing made up like 6 marks of last years paper, doubt it'll be on esterification pracs.

agreed on the eutrophication/water quality prac questions, which is unfortunate since i was away when we did them in class haha just my luck
 
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idk refluxing made up like 6 marks of last years paper, doubt it'll be on esterification pracs.

agreed on the eutrophication/water quality prac questions, which is unfortunate since i was away when we did them in class haha just my luck
The pracs are simple. Most take like 2 seconds.

You have to elaborate on what i've written below, but in simple terms.

Water Hardness - chuck soap flakes in soft water and hard water. Soft water = froth, Hard water = small powder (scum aka calcium stearate) at bottom of test tube. Titration with EDTA (also not done by most schools, just got to know the ratio is 1:1, ratio of Calcium ions to EDTA ions
Turbidity - using a turbidity column, pour water in until you cannot see the "X" at the bottom, read of measurement on the column.
pH - pH meter or pH probe attached to a data logger.
Ions - precipitation
BOD - Gather water, measure the dissolved oxygen concentration. Place in brown blag, place in the dark for 5 days. Measure DO again, difference in DO levels = BOD.
Total Dissolved Solids - using a conductivity meter or evaporation of water sample.
DO - using oxygen sensitive electrode or Winkler titration (titration which you do not do at school, too long and complex)
 
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iStudent

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The pracs are simple. Most take like 2 seconds.

You have to elaborate on what i've written below, but in simple terms.

Water Hardness - chuck soap flakes in soft water and hard water. Soft water = froth, Hard water = small powder (scum aka calcium stearate) at bottom of test tube. Titration with EDTA (also not done by most schools, just got to know the ratio is 1:1, ratio of Calcium ions to EDTA ions
Turbidity - using a turbidity column, pour water in until you cannot see the "X" at the bottom, read of measurement on the column.
pH - pH meter or pH probe attached to a data logger.
Ions - precipitation
BOD - Gather water, measure the dissolved oxygen concentration. Place in brown blag, place in the dark for 5 days. Measure DO again, difference in DO levels = BOD.
Total Dissolved Solids - using a conductivity meter or evaporation of water sample.
DO - using oxygen sensitive electrode or Winkler titration (titration which you do not do at school, too long and complex)
My school actually ended up doing both of those titrations (edta+Winkler). But teacher said we don't have to know them.
 

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