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[Lord Ac]

Thanks for any help anyone can provide. Ive got a CRAP-LOAD of questions to do on all the Mod. 2 pracs and these ones are causing me to swear!!

1a. Today, Carbon dioxide is supplied to the bottling plant in tanks of liquid CO2. Why isnt compressed CO2 gas used?

b. Under what specific conditions does liqiod CO2 exist?

2a. What generalisations can be made about the pH of chemicals used for cleaning? Why is this pH range effective for cleaning?

b. What generalisations can be made about the pH of foods? (eg. mustard pickles, lemon juice)? Why is this pH range effective for food preservation?

3a. NaHSO4 solution is acidic. Why is Na2SO4 nuetral?

b. NaHCO3 solution is basic. Why is Na2CO3 also basic?

4a. Describe the natural process of making vinegar.

b. Vinegar is a common preservative, used in pickles and other foods. Explain how vinegar works in this application.

Thanks in advance!

Ac

 

[Lord Ac]

Anybody; any question!??!

Ac

 

[Ragerunner]

1a. Today, Carbon dioxide is supplied to the bottling plant in tanks of liquid CO2. Why isnt compressed CO2 gas used?

i dunno. maybe because to actually compress it into a bottle is pretty hard and has to be done in some factory.

2a. What generalisations can be made about the pH of chemicals used for cleaning? Why is this pH range effective for cleaning?

Bases are used. dunno about why

b. What generalisations can be made about the pH of foods? (eg. mustard pickles, lemon juice)? Why is this pH range effective for food preservation?

it has to be acidic to prevent bacteria from forming. but the strength of the acid is limited so it doens't last forever. mention shelf life.

3a. NaHSO4 solution is acidic. Why is Na2SO4 nuetral?

goes something like
strong base + weak acid = basic
strong acid + weak base = acidic
strong base + stong acid = neutral

b. NaHCO3 solution is basic. Why is Na2CO3 also basic?

same reason

4a. Describe the natural process of making vinegar.

dunno. get some acid and add some stuff to it

b. Vinegar is a common preservative, used in pickles and other foods. Explain how vinegar works in this application

its highly acidic. it prevents bacteria from forming.


sorry if my answers are of ZERO help

 

[Toodulu]

Originally posted by Lord Ac

1a. Today, Carbon dioxide is supplied to the bottling plant in tanks of liquid CO2. Why isnt compressed CO2 gas used?

b. Under what specific conditions does liqiod CO2 exist?

i think it might have something to do with the carbon dioxide equilibrium.
CO2 is slightly soluble in water, and the dissolved CO2 reacts with water to form a weak carbonic acid.
liquid CO2 would exist when CO2 is dissolved in water (?)
CO2(g) (double arrow) CO2(aq)

i dont think that answers the question though...

3a. NaHSO4 solution is acidic. Why is Na2SO4 nuetral?

b. NaHCO3 solution is basic. Why is Na2CO3 also basic?

talk about the acids/bases that form those salts and their strengths?