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Chemistry: Post your doubts here!

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why not A? al203 makes a complex right? i.e sodium aluminate ( NaAlOh4... is that considered a salt too?
 

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how to decide between Nacl and MgO about which one will have a higher M.P/B.P
 

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yup its N2014/11

but is NaAlOh4 considered a salt?

Yes. NaAlOH4 is a salt.

I'm surprised it can react with cold NaOH.

But having reread the question and having to choose between Al2O3 and SiO2, I guess SiO2 is more unreactive due to its giant covalent structure.
 
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upload_2015-5-28_16-36-54-png.54149


How to do this one??
 
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How to do this one??

for option 1
62/100*74 =45.88 of butan-2-ol actually reacted to form butanone. The number of moles of the reacted butan-2-ol are hence 45.88/74(Mr of butan-2-ol) = 0.62 moles. The number of moles of alcohol reacted will be equal to number of moles of ketone formed. Hence mass of butanone is 0.62 moles*72= 44.64g Hence statement 1 is correct.
For option 3
again 62% of 74g is 45.88g of the alcohol hence the number of moles will be 45.88/74(Mr of 2-methyl alcohol)=0.62 moles. As moles of reactant in this case is equal to moles of product, the mass of acid is 0.62*88= 54.56g. Hence statement 3 is correct. If 1 and 3 are correct the answer is for sure A
 
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