Hsc Marathon 2009 - Chemistry (4 Viewers)

[gifted:)]

litmus, methyl orange, phenolphthalein, bromothylmol blue just to name a few ...

Q. identify the species in a bottle of soda

 

[Kaatie]

what do you mean by species? carbon dioxide?
obviously i havent covered this yet...

 

[shady145]

i dunno what u mean by species either my first guess is what kaatie is talking about.

 

[Pwnage101]

chemical species...

 

[shady145]

^
your smart, does species just mean the molecules that are in the soda?
or does your response mean you dnt know what it means either?

 

[marcquelle]

i think chemical species means what type of chemical it is eg oxides, salts etc

 

[gifted:)]

sorry comp was screwed up ... my chem teacher says species refers to atoms, ions molecules elements etc.

when he first asked us what are the species in a bottle of soda, we all went blank, sorry for the delay!

hint: carbonic acid and H ions

 

[Pwnage101]

sorry comp was screwed up ... my chem teacher says species refers to atoms, ions molecules elements etc.

when he first asked us what are the species in a bottle of soda, we all went blank, sorry for the delay!

hint: carbonic acid and H ions

yeh that's what we mean by 'species' in chemistry

ofcourse you could have googled it or gone to Wikipedia

 

[Kaatie]

three questions here:
1) DIscuss the evidence for the assertion that the quantities of nitrogen oxides and sulfur dioxide released into the atmosphere are increasing

2) Explain why acid rain problems occur mainly in areas of high population density and industrial intensity or downwind from such areas

3) balanced symbol eqn for chromium (III) hydroxide and sodium hydroxide solution

 

[aero135]

1) Ice core samples, increased effects of CO2 picked up in some animal whose name i forget.

 

[imoO]

three questions here:
1) DIscuss the evidence for the assertion that the quantities of nitrogen oxides and sulfur dioxide released into the atmosphere are increasing

2) Explain why acid rain problems occur mainly in areas of high population density and industrial intensity or downwind from such areas

3) balanced symbol eqn for chromium (III) hydroxide and sodium hydroxide solution

Acid rain usually occurs mainly in areas of high population and activity because these areas produce the most nitrogen and sulfur emissions. These increased emissions contribute to the formation of acid rain in the atmosphere when it reacts with moisture or water in the air, and forms acid rain.

 

[kevda1st]

Starch - polymer
glucose - polymer
ethene - monomer
polyethene - polymer



Describe how a geiger counter works.

 

[adnan91]

nah dawg glucose is a monomer

 

[gifted:)]

Beta ray entrs through a thin end window of the gieger tube where it hits a gas molecule (argon mostly) and ionises it by knocking an electron out of it. the high voltage accelerates this electron towards the central electrode andas it gains speed, it ionises more argon atoms in its path so there is a cascade of electrons reaching that electrode. This constitutes an electrical pulse which is amplified and measured by generating clicks in an audio amplifier.

Q. Give an equilibrium reaction of CO2 and H2O with states

 

[Aerath]

Describe and explain galvanic cells in terms of oxidation and reduction reactions.

 

[gifted:)]

wow, no one has answered this q for a while.... i know minimal info on electrochem! someone answer!!!!!!!!!!!!!!!!!

 

[Continuum]

Nobody answered it because to fully explain it, you'd need to write a fair bit.

 

[Pwnage101]

i'd answer it, but i'm an 08er, i'm leavin it to you guys (since it is YOUR revision thread) ....

 

[gifted:)]

someone post a diff question, this site is my second revision for my chem half yearly!

 

[gifted:)]

aa .... i finished my chem half yearly last thursday, have fun studyin

p.s. my chem teacher pulled half the multiple choice questions from the 2008 HSC paper!