Chemistry: Post your doubts here!

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But the problem is , isn’t the entalphy change is only needed for C2H2. Here it gives C2H2 and H2
In the Transformation of carbon and hydrogen to ethyne we need 2 moles of Carbon and 1 mole of hydrogen . The other mole of hydrogen is not used in the reaction and hence the change in enthalpy of that step is zero . I hope you can see in the picture
 

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Is there any easy was to calculate isomers ? It gets so confusing. And , can anyone explain stereoisomerism ( like for the geometric one, should there be 2 same group to depict the cis and trans , or the hydrogen can be considered) ?
 
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Hi guys, I am Mr Onn, a chemistry teacher based in Brunei. I teach A Level Chemistry based on the Cambridge International curriculum but between the different A Level examination bodies, the contents are not too different overall.



I have made some tutorial videos on tackling multiple choice questions, which can be tricky sometimes. In these hour length videos, you can skip to the relevant question(s) of interest with the chapter marker in the video description section on YouTube.



Check out my channel on YouTube. Do subscribe and like the videos to receive more great content in the future. I have plans to cover IGCSE and Ordinary Level (Cambridge International) papers too in the future.




You can also follow via other social media platforms

IG/FB/Twitter ptet.chemistry

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Cheers.
 
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Hi guys! Does anyone know how to access save my exam mark schemes for free? I really need them for practice in Chemistry (0620), Physics (0625), and Maths (0580), and my parents refused to buy them for me. Can you please help me? I will be eternally in debt if you forward them or suggest links at [email protected] Thanking you in anticipation!!
 
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Hi guys! Does anyone know how to access save my exam mark schemes for free? I really need them for practice in Chemistry (0620), Physics (0625), and Maths (0580), and my parents refused to buy them for me. Can you please help me? I will be eternally in debt if you forward them or suggest links at [email protected] Thanking you in anticipation!!
just type the search words in google and you will find them all
 
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