The Ultimate Thread of CHemistry Question HSC 2006 (1 Viewer)

[.ben]

Hey wit the ach ess cee coming in about 2 weeks I thought it would be good to have a thread where the kind people of this thread would answer random questions?

Post ur questions. I'll get us started:

1. Do we actually have to known an example of a CFC and equations involved?

2. How do you calculate the pH of acids with same molarity?

3. How much do we have to know about transuranic elements?

4. What are ALL the equations for the fermentation experiment?

5. What do the terms v/v or v/w or w/w mean?

6. In the development of acid and base theories, do we have to know about the contributions of Faraday?

7. How much detail do we need for EDTA titration?

8. What kind of reliability and validity do we need for the content of sulfate in fertiliser experiment?

 

[kazan]

1. yes

2. i dont know that either

3. "describe how transuranic elements are produced"
"process information from secondary sources to describe the recent discovery of elements"

4..

5..

6. no we need lavosier, davy, arrhenius and bronsted lowry ( sp :s )

7. ...

8.. i dont understand the question, are you asking how we can judge the reliability and validity, or what can effect these?



my question

from the CSSA 06 trial

explain how an understaning of electron transfer reactions can be used to clarify the role of bacteria in accelerating the corrosion of deeply submerged wrecks. ( 6 marks)

 

[Ennaybur]

i haff no answers 4 joo

 

[passion89]

my question

from the CSSA 06 trial

explain how an understaning of electron transfer reactions can be used to clarify the role of bacteria in accelerating the corrosion of deeply submerged wrecks. ( 6 marks)

Awww only people who've done Shipwrecks can answer that question - Ask questions from the core topics because then anyone can have a go at answering them

 

[Riviet]

How do you calculate the pH of acids with same molarity?

Check how many hydrogens are in their formula and multiply molarity by that amount before applying the log formula. e.g sulfuric acid contains 2 H's (diprotic), so you multiply molarity by 2.

In the development of acid and base theories, do we have to know about the contributions of Faraday?

According to the syllabus, no.

What kind of reliability and validity do we need for the content of sulfate in fertiliser experiment?

Increase reliability by repeating the procedure
The experiment is not valid because the filter paper lets the fine powder through.

 

[Tim035]

Hey wit the ach ess cee coming in about 2 weeks I thought it would be good to have a thread where the kind people of this thread would answer random questions?

Post ur questions. I'll get us started:

1. Do we actually have to known an example of a CFC and equations involved?

2. How do you calculate the pH of acids with same molarity?

3. How much do we have to know about transuranic elements?

4. What are ALL the equations for the fermentation experiment?

5. What do the terms v/v or v/w or w/w mean?

6. In the development of acid and base theories, do we have to know about the contributions of Faraday?

7. How much detail do we need for EDTA titration?

8. What kind of reliability and validity do we need for the content of sulfate in fertiliser experiment?

1. For CFC's you should know the chain reaction that involves them destroying ozone in the stratosphere and be able to name a CFC if graphically presented with its molecular formula.

2. Already answered... more likely though theyll give you a neutralisation equation (most likely one that gives a netural salt) with either the acid or base in excess and ask u to calculate the pH of the final solution.

3. How their made, why they can be made through different processes compared to radioisotopes (hint: neutrons & electron bombardment) and an example with preferably the chemical equation to support it (hint: uranium to neptunium)

4. U should know the glucose to ethanol and CO2.. and then Ethanol aqueous to ethanol high% by distillation.

5. No idea unless its another version of the CB x VB/NB = CA x VA/NA or c1v1=c2v2

7. Isn't EDTA a substance used to treat people with lead poisoning??
For a titration prac I'd just know the good old ethanoic acid vs sodium hydroxide with phenopthalein indicator.

8. Conquering chem does this really well, go look it up and make some notes.

 

[lala2]

5. I'm assuming you mean %v/v, %v/w, and %w/w? If so, it's just a percentage of solute in "solvent", i.e. solute/100 product (so product is substance A + B + C+ ....), where v is volume and w is weight, e.g. 7%w/w is 7 grams of "solute" for every 100grams of product, or 7%v/w is 7 mls of "solute" for every 100grams of product.