• Best of luck to the class of 2024 for their HSC exams. You got this!
    Let us know your thoughts on the HSC exams here
  • YOU can help the next generation of students in the community!
    Share your trial papers and notes on our Notes & Resources page
MedVision ad

Evidence for increases in atmospheric oxides? (1 Viewer)

Schoolboy

New Member
Joined
Nov 9, 2007
Messages
8
Gender
Male
HSC
2008
The syllabus dot point is:
Assess the evidence which indicates increases in atmospheric concentration of oxides of sulfur and nitrogen.
Are we ment to talk about the Industrial Revolution (i.e. history), or are their chemistry related tests that show this. Its an assess, so I need pro's and cons, I guess.
Ultimately, I have no idea what to write lol
<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:eek:ffice:eek:ffice" /><o:p></o:p>
 

samwell

Member
Joined
Nov 19, 2007
Messages
400
Gender
Male
HSC
2008
Check HSC online. Thanx for the post i think my response to this dot point would lose me some marks. but basically i think u have to give a jugdement on the evidence amd consequences of increased pollution.
 

JasonNg1025

Member
Joined
Oct 14, 2007
Messages
295
Gender
Male
HSC
2010
HSC Online tends to skip some stuff, and I can't be bothered to check if it has this time :p

I think first you talk about the actual evidence which indicates increases in atmospheric concentration of oxides of sulfur and nitrogen... that is, holes are drilled in Antarctic ice where these gases formed air bubbles. New ice formed is up the top, so the layers of ice further down are older, whereas the layers further up are newer. By analysing the amount of oxides of sulfur and nitrogen at different levels, you can find trends which can indicate increase in the atmospheric concentration of the oxides. An increase in acid rain also indicates this as the gases are a major contributor to acid rain. A brownish smog thingy also indicates nitrogen oxides.

You also need to talk about the difficulties in doing so. The equipment for analysis was only available from... the 1970s? I forgot, but it was pretty recent, so you could say that trends have been difficult to detect due to the short period of analysis time. Also, the concentrations are really small, like 0.001ppm in populated areas or something.

I gotta check up on this too... guess I'll check HSC Online now :D

EDIT: Ok, HSC online has a little more stuff, but for some reason talks about CO<sub>2</sub> a lot. I must be missing something...
 

minijumbuk

┗(^o^ )┓三
Joined
Apr 23, 2007
Messages
652
Gender
Male
HSC
2008
JasonNg1025 said:
HSC Online tends to skip some stuff, and I can't be bothered to check if it has this time :p

I think first you talk about the actual evidence which indicates increases in atmospheric concentration of oxides of sulfur and nitrogen... that is, holes are drilled in Antarctic ice where these gases formed air bubbles. New ice formed is up the top, so the layers of ice further down are older, whereas the layers further up are newer. By analysing the amount of oxides of sulfur and nitrogen at different levels, you can find trends which can indicate increase in the atmospheric concentration of the oxides. An increase in acid rain also indicates this as the gases are a major contributor to acid rain. A brownish smog thingy also indicates nitrogen oxides.

You also need to talk about the difficulties in doing so. The equipment for analysis was only available from... the 1970s? I forgot, but it was pretty recent, so you could say that trends have been difficult to detect due to the short period of analysis time. Also, the concentrations are really small, like 0.001ppm in populated areas or something.

I gotta check up on this too... guess I'll check HSC Online now :D

EDIT: Ok, HSC online has a little more stuff, but for some reason talks about CO<sub>2</sub> a lot. I must be missing something...
Aren't you in year 10? lol
 

syriangabsta

Member
Joined
Feb 27, 2007
Messages
297
Gender
Male
HSC
N/A
heres some pointers

-analysis of antartic ice core samples
-increasing dmg to buildings
-increase in acid rain
-increase of acidity of rivers and lakes
 

JasonNg1025

Member
Joined
Oct 14, 2007
Messages
295
Gender
Male
HSC
2010
minijumbuk said:
Aren't you in year 10? lol
Yes... I do year 12 Chemistry though :D

Oh yeah, I forgot about decreasing pH of water bodies... should remember that too
 

tommykins

i am number -e^i*pi
Joined
Feb 18, 2007
Messages
5,730
Gender
Male
HSC
2008
回复: Re: Evidence for increases in atmospheric oxides?

• It has been observed that the damage to buildings, forests, and aquatic organisms is increasing, and this is thought to be due to acid rain, which is formed by the mentioned oxides reacting with water in the atmosphere.
• Also, there has been an increase in the acidity of rivers and lakes. Higher atmospheric concentrations of sulfur and nitrogen oxides have been detected in industrial areas as compared to non-industrial areas. Note that Sydney’s air does not suffer the extreme levels of pollution found in large industrialized centres of Europe and the USA. This is partly due to the low sulfur content in Australian coal.
• Difficulties in gaining such evidence should also be noted. For instance, the very small atmospheric concentrations of sulfur and nitrogen oxides have resulted in these minute concentrations being only detectable from the 1970s after the advent of sufficiently sensitive instruments. Also, sulfur dioxide and nitrogen dioxide are readily soluble in water, meaning they can circulate in the biosphere and hydrosphere. This results in any atmospheric measurements of their presence inaccurate and their validity questionable.
• Hence although accurate measures of atmospheric oxides of sulfur and nitrogen are at present non-existent, there is sufficient indirect evidence to conclude that significant increases in the atmospheric concentrations of oxides of sulfur and nitrogen have indeed taken place, especially after industrialization.
 

JasonNg1025

Member
Joined
Oct 14, 2007
Messages
295
Gender
Male
HSC
2010
Re: 回复: Re: Evidence for increases in atmospheric oxides?

I guess the information is confirmed then ;D
 

samwell

Member
Joined
Nov 19, 2007
Messages
400
Gender
Male
HSC
2008
JasonNg1025 said:
Yes... I do year 12 Chemistry though :D

Oh yeah, I forgot about decreasing pH of water bodies... should remember that too
if u continue doing what ua doing expect a really high hsc mark. Good luck in the coming yrs
 

JasonNg1025

Member
Joined
Oct 14, 2007
Messages
295
Gender
Male
HSC
2010
Yesh, tommykin's one is easier to remember because of dot points. Also, it contains a little more information and sentence structure
 

JasonNg1025

Member
Joined
Oct 14, 2007
Messages
295
Gender
Male
HSC
2010
I'm pretty sure the dot point asks for SO<sub>2</sub> and NO<sub>x</sub>. Check the dot point I guess... the methods they use should be the same though ;P
 

syriangabsta

Member
Joined
Feb 27, 2007
Messages
297
Gender
Male
HSC
N/A
crammy90 said:
yeh do u rekon we should know about CO2?
well the dot point specifically asks for concentration of oxides of sulfur and nitrogen.

so, no you wouldnt need too. but if u have time, it wouldnt hurt to shove it in thier lol, itll show the markers you know what you're on about...besides its not like you're wasting time studying it, you should know all about it from an earlier dot point (le chatleiers principle and CO2)
 

JasonNg1025

Member
Joined
Oct 14, 2007
Messages
295
Gender
Male
HSC
2010
Well, you wouldn't know about it in this context. You could shove it in as an aftercomment like levels of CO<sub>2</sub> can also be detected in this way or something similar...
 

emmcyclopedia

Member
Joined
Oct 7, 2008
Messages
391
Gender
Female
HSC
2009
Yes... I do year 12 Chemistry though :D

Oh yeah, I forgot about decreasing pH of water bodies... should remember that too
what a legend.
you actually did maths ext 1/2 in yr 9....frig, i do ex 1 now and find it mentally tiring! you did it in yr 9?
you are my hero.

btw, good thread guys, helpin the mid-yearlies chem revision
=0
 

Users Who Are Viewing This Thread (Users: 0, Guests: 1)

Top