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How can I improve my chemistry grades drastically Watch

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    My issue isn't the content in chem AS, in class I understand everything and can explain any concepts we've learnt but when we do unit tests I just can't do them? I feel like the questions are soooo much harder than what I've learnt and idk how to overcome this, I've tried using past papers but my grades are still slipping I started the year with a B and am now working at a D... I've just arranged a tutor but idk if that will help seeing as I understand all the content, does anyone have any tips??
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    are you sure you understand the content? Surely, if you don't answer the questions you don't get the content?
    (Original post by _princessxox)
    My issue isn't the content in chem AS, in class I understand everything and can explain any concepts we've learnt but when we do unit tests I just can't do them? I feel like the questions are soooo much harder than what I've learnt and idk how to overcome this, I've tried using past papers but my grades are still slipping I started the year with a B and am now working at a D... I've just arranged a tutor but idk if that will help seeing as I understand all the content, does anyone have any tips??
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    If you know it, explain why hydrogen sulphide is a gas but water is a liquid at room temperature.
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    (Original post by 1jonam16)
    are you sure you understand the content? Surely, if you don't answer the questions you don't get the content?
    Idk like when I do my corrections I'm always like oh I knew this or I knew what this was but when I'm actually doing the tests I just don't know why I can't answer it and get all the marks, I feel pretty confident with content in class and tbh I'm doing a lot better than most girls in my class which is why I think the school may just be writing is very hard exam questions but idk I want to be working at a B or A at least
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    Read the mark schemes so you know how to exactly answer a question and how to get the marks
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    Past papers, past papers and past papers. I can't stress this enough but the practice of actual exam questions boosts your grades so much
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    (Original post by _princessxox)
    My issue isn't the content in chem AS, in class I understand everything and can explain any concepts we've learnt but when we do unit tests I just can't do them? I feel like the questions are soooo much harder than what I've learnt and idk how to overcome this, I've tried using past papers but my grades are still slipping I started the year with a B and am now working at a D... I've just arranged a tutor but idk if that will help seeing as I understand all the content, does anyone have any tips??
    I'm assuming ur struggling with the exam style questions so I recommend doing loads of past papers or spec papers and checking the mark scheme afterwards
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    (Original post by Maker)
    If you know it, explain why hydrogen sulphide is a gas but water is a liquid at room temperature.
    Is it due to the fact that h2o makes hydrogen bonds and is more polar than h2s
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    (Original post by TheGoodPharaoh)
    Read the mark schemes so you know how to exactly answer a question and how to get the marks
    Okay thank you I'll try to do this
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    (Original post by ffx_)
    Past papers, past papers and past papers. I can't stress this enough but the practice of actual exam questions boosts your grades so much
    Yeah I've been trying this but I feel like it's the application that I find hard in questions that I haven't seen before :/ like it kind of puts me off when I don't know exactly what a question is asking for
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    (Original post by BröwnSigatøka)
    I'm assuming ur struggling with the exam style questions so I recommend doing loads of past papers or spec papers and checking the mark scheme afterwards
    Thank you
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    (Original post by _princessxox)
    Is it due to the fact that h2o makes hydrogen bonds and is more polar than h2s
    That is a partial answer, you need to explain why is water more polar than H2S and what about molecular weight?

    Marking schemes give marks for explaining the answer, not just the answer. Giving half the answer would give you a C or B grade, a full answer explaining the reasons will give you an A* grade.
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    (Original post by Maker)
    That is a partial answer, you need to explain why is water more polar than H2S and what about molecular weight?

    Marking schemes give marks for explaining the answer, not just the answer. Giving half the answer would give you a C or B grade, a full answer explaining the reasons will give you an A* grade.
    Water is more polar than H2S due to the electronegativity difference between S and O. Oxygen is more electronegative, therefore it has the ability to attract more electron density to inducing a partial negative charge upon itself and leaving the hydrogen's with a partial positive charge. The opposite charges attract to each other and due to the large difference in polarity and the bonding with hydrogen is susceptible to Hydrogen bonding. On the contrary, H2S undergoes Dipole-Dipole Interaction due to the fact the Sulphur atom is not electronegative enough to make a hydrogen bond furthermore, Dipole-Dipole Interaction is much weaker than Hydrogen bonding. The hydrogen bond requires more energy to break hence the reason why Water is a gas at room temperature?



    Leave me feedback on my answer please.
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    (Original post by Bulletzone)
    Water is more polar than H2S due to the electronegativity difference between S and O. Oxygen is more electronegative, therefore it has the ability to attract more electron density to inducing a partial negative charge upon itself and leaving the hydrogen's with a partial positive charge. The opposite charges attract to each other and due to the large difference in polarity and the bonding with hydrogen is susceptible to Hydrogen bonding. On the contrary, H2S undergoes Dipole-Dipole Interaction due to the fact the Sulphur atom is not electronegative enough to make a hydrogen bond furthermore, Dipole-Dipole Interaction is much weaker than Hydrogen bonding. The hydrogen bond requires more energy to break hence the reason why Water is a gas at room temperature?



    Leave me feedback on my answer please.
    That is a good answer, you should also mention the lone pairs of electrons on the oxygen atom and that sulfur has a higher atomic weight than oxygen which should increase its boiling point but hydrogen bonding has a bigger effect than atomic weight.
    For a complete A* quality answer, I would also expect an explaination of why oxygen is more electro negative than sulfur i.e. the effects of their electron configurations.
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    (Original post by Maker)
    That is a partial answer, you need to explain why is water more polar than H2S and what about molecular weight?

    Marking schemes give marks for explaining the answer, not just the answer. Giving half the answer would give you a C or B grade, a full answer explaining the reasons will give you an A* grade.
    I only just covered this topic yesterday lol
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    Work harder and better.
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    (Original post by Maker)
    That is a good answer, you should also mention the lone pairs of electrons on the oxygen atom and that sulfur has a higher atomic weight than oxygen which should increase its boiling point but hydrogen bonding has a bigger effect than atomic weight.
    For a complete A* quality answer, I would also expect an explaination of why oxygen is more electro negative than sulfur i.e. the effects of their electron configurations.
    Explain
 
 
 
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