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AQA GCSE CHEMISTRY Unit 1 Question Game!

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Original post by 4dam
How has the concentration of different gases in the atmosphere changed over time?


Carbon dioxide levels significantly decreased -> due to formation of plants and algae using them for photosynthesis. Also this CO2 is locked up in fossil fuels and dissolved in oceans.

Ammonia converted into nitrogen in todays early atmosphere and water vapour condensed, forming oceans. Methane ??
Reply 161
Original post by 4dam
How has the concentration of different gases in the atmosphere changed over time?


Lots of CO2 early on as they were released from volcanoes.
Then less CO2 as they dissolved in seas/oceans and plants/algae used them for photosynthesis.
Even less nowadays, the air consists now of around 21% Oxygen and 78% Nitrogen.
Original post by kefalos23
Easy one : What is the atomic and mass number of an element?

atomic number = number of protons
mass number - the mass of the neutron basically so no. of protons + no. of neutrons
Original post by GeorgeMillerr
A drunk rat?


Omg 😂 Who knows it might come up tomorrow knowing aqa
Original post by GeorgeMillerr
Using only the revision guide is a bad idea
The REVISION GUIDE WAS MADE IN 2011!!!
The Specification was made in 2014!!!
- new topics have arose since then and old ones removed
- the exam board make the specification whereas the CGP guide was made by a 'Independent company'
*see what i did there with the pun xD


Yeah, I know but if that's the one that your school tells you to revise from, what can you do?
Yeah, that pun was pretty good :h:
Original post by GeorgeMillerr
Well I will guarantee there wont be anything about metal stress, this will resume tomorrow when my point is proven


You're Probs right mate, I'm just sticking with the crap I know
Original post by 4dam
How has the concentration of different gases in the atmosphere changed over time?


Then : carbon dioxide, ammonia, methane and water vapour
Now : oxygen 21% nitrogen 78% 1 % of other gasses
Reply 167
Original post by kefalos23
Easy one : What is the atomic and mass number of an element?


Atomic number - Number of protons
Mass number - Number of protons plus neutrons
Can someone link me the spec?
Apparently the 6 marker is on quarrying advs + disadvs
What happened to Ammonia,Methane and argon in early atmosphere - to todays atmosphere.
Reply 171
What is cracking and how does it work?
image.jpegSorry guys, just a moral booster.
Going bed, gnight all! Good luck in your exam(s) tomorrow!!! Xxx
Reply 174
Original post by IAmAnTroll
Apparently the 6 marker is on quarrying advs + disadvs


Thats what im assuming as well, could be on + and - of extracting metals, but they are both similar
Original post by Obnox
What is cracking and how does it work?


Cracking is the process of breaking large/long chain molecules of ALKANES into shorter chain ALKANE and an ALKENE. This is done at a high temperature and presence of catalyst.
Explain how vegetable oils are extracted from plants?
Reply 178
Original post by whyaqawhy
Cracking is the process of breaking large/long chain molecules of ALKANES into shorter chain ALKANE and an ALKENE. This is done at a high temperature and presence of catalyst.


Nice, vaporised and passed over a catalyst of aluminium oxide, done at a high temp. :smile:
What do hydrocarbons contain (2 marks)?

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