Chemistry: Post your doubts here!

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Ans is c but why..
I'm not that good in chemistry, but from my understanding it cant be a,b, or d because these three properties are also present in NaCl and MgO and the question says that CsCl has a different structure than these two, so the only distinct property that CsCl has is the radii ratio.
 
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I'm not that good in chemistry, but from my understanding it cant be a,b, or d because these three properties are also present in NaCl and MgO and the question says that CsCl has a different structure than these two, so the only distinct property that CsCl has is the radii ratio.
Let me know if this helped.
 
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One mole of sulfuric acid is used to make an aqueous solution. The solution contains H2SO4
molecules, H+ ions, SO4 2– ions and HSO4– ions.
Which statements are correct?
1 The solution contains 6.02 × 1023 sulfur atoms.
2 The solution contains an exactly equal number of H+ ions and HSO4– ions.
3 One mole of SO4 2– ions contains two moles of electrons.
answer is D means only option 1 is correct. plz justify
 
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Hello fellow students, if you or someone else you know are preparing for O-Level or A-Level chemistry this October/November 2020, or sometime in the future, please check out my YouTube channel where I feature step-by-step tutorial videos on my thought processes in addressing the examination papers across the different variants of the Cambridge International curriculum.


Even if your zone(s) is/are set to sit for a specific variant, it never hurts to check out the same curriculum in other variants for practice. Please subscribe to the channel to support this not-for-profit endeavour. Also, please spread the words to your friends/teachers/contacts to benefit more students like yourself.

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First write the balanced equation.
2H2S + 3O2 ------> 2H2o + 2SO2
(Note:For AS you're not required to know this equation by heart but whenever such a question appears, there are either hints in it about the products or the products are stated explicitly. Nonetheless, you're expected to know the oxidation/combustion products of H2 and S2. )
Moles of H2S = Mass/Molar Mass = 8.65/((32.1 + 2) = 173/682
Moles of O2 = (3 x (173/682))/2 (since mole ratio H2S:O2 = 2:3 from the equation) = 519/1364
Volume = moles x 24 = (519/1364) x 24 = 9.13 dm^3
 
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Hi all, I have added more short tutorial videos covering specific concepts, like quick-bites with worked examples, explaining step-by-step how to proceed with calculations/explanations. These complement the longer videos that cover full past paper tutorials.


My videos/YouTube channel try to achieve more than just solving a paper or following mark scheme. Some have found some mistakes within, which is good. The viewers are learning! I don't usually try to correlate to mark schemes, and hey mistakes are common, but I try to minimise mine of course.

If you like my teaching style/explanations, please subscribe to the channel. Do drop comments if there are areas you wish me to cover. Learning chemistry is more than just about acing the exams. If you understand the story behind the concepts, then you will get the grades naturally.
 
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Hi all, I have added more short tutorial videos covering specific concepts, like quick-bites with worked examples, explaining step-by-step how to proceed with calculations/explanations. These complement the longer videos that cover full past paper tutorials.


My videos/YouTube channel try to achieve more than just solving a paper or following mark scheme. Some have found some mistakes within, which is good. The viewers are learning! I don't usually try to correlate to mark schemes, and hey mistakes are common, but I try to minimise mine of course.

If you like my teaching style/explanations, please subscribe to the channel. Do drop comments if there are areas you wish me to cover. Learning chemistry is more than just about acing the exams. If you understand the story behind the concepts, then you will get the grades naturally.
 
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