Trial HSC Question (1 Viewer)

[Kukudas]

I was never sure of this dot point and i saw a question on this dot point
in past trial papers;;

Q. Describe how information about changing atmospheric ozone concentration is obtained (3marks)

Can anyone help me??

 

[BIGTYMA]

The concentration of air pollutants are collected through RPI (regional pollution indexes). RPI is calculated 2 twice a day (day and night time).

Chemistry In Context 2. page 243

 

[jlnWind]

I was never sure of this dot point and i saw a question on this dot point
in past trial papers;;

Q. Describe how information about changing atmospheric ozone concentration is obtained (3marks)

Can anyone help me??

Hey um, theres another thread for this same question, but heres how i depic the marking criteria

Describe- identify characteristics and features?

soo...
1 mark- describing methods (technologies) used to obtain the data
these included (at the time 1970s) ground based UV spectrometers as well as air samples.
1 mark- what they noticed: Drop in ozone levels over Antarctica- In 1976 (initial readings of 10% loss) - 1985 (50% loss) indicating it was no coincidence or malfunction in technology, or natural events such as sunspot activity.
1 mark- Identifying some new forms of technology used- UV lasers fired from ground, satellites using infrared radiometers, total ozone mapping spectrometer (TOMS) from Nasa. New techniques improve reliability of collected data and demonstrate that ozone loss is a real phenomenon.

 

[xiao1985]

In short:

TOMS: Total Ozone Mapping Spectrophotometry (in CCHSC),
A satellite generated image which shows ozone conc.

or spectrophotometer on a weather balloon and compare it with the value getting on ground level. The difference of UV intensity is indicative of ozone conc.


edit: re above: nice answer. Though for a describe question, I don't think you need to go into if it's reliable or not.

 

[wrxsti]

i answered this in godfreys thread

 

[jlnWind]

In short:

TOMS: Total Ozone Mapping Spectrophotometry (in CCHSC),
A satellite generated image which shows ozone conc.

or spectrophotometer on a weather balloon and compare it with the value getting on ground level. The difference of UV intensity is indicative of ozone conc.


edit: re above: nice answer. Though for a describe question, I don't think you need to go into if it's reliable or not.

oh yeh i dont think id go into it, but maybe mentioning (like that sentence only)? or??