-
We need your support!
We are currently struggling to cover the operational costs of Xtremepapers, as a result we might have to shut this website down. Please donate if we have helped you and help make a difference in other students' lives!
Click here to Donate Now (View Announcement)
Search results
-
Chemistry: Post your doubts here!
do we not need to draw any cycle here? -
Chemistry: Post your doubts here!
Its winter 2011 p22; could u please check? -
Chemistry: Post your doubts here!
wow, you just cleared my concept. thank you! Okay, just one more please :) We have to draw the Hess's law here. In b(iii), we found enthalpy change of K2CO3, it was -32.6 kJ/mol and in c(iii), we found enthalpy change of KHCO3, it was +23.19 kJ/mol , can you please draw the Hess's cycle for... -
Chemistry: Post your doubts here!
thank u so much I get that...here is another Question is : Compound A is a liquid which does not react with 2,4-DNPH reagent or with aqueous bromine. Suggest two structural formula of A. (We found the molecular formula in previous part which was C2H4O2) Here is what the markscheme says It's... -
Chemistry: Post your doubts here!
So precipitate with aquous silver nitrate means that could be any of the halogens but what does solubility with aquous ammonia tell about? -
A level Biology: Post your doubts here!
oh yes you guys are right :( -
A level Biology: Post your doubts here!
yep, as per your instructions I do read ERs now, but this one, I was just solving yet and this question was buggin me a lot. But the thing is we didn't learn this in the syllabus! did we? I read both books more than once and not a single word about photosynthesizing prokaryotes was mentioned... -
A level Biology: Post your doubts here!
How comes photosynthetic prokaryotes do not need chloroplasts to photosynthesize? It's C -
Mathematics: Post your doubts here!
The signs in the solution are quite difficult to type, so I did it handwritten, here you go -
-
Mathematics: Post your doubts here!
You need to plan and categorize your study. The first thing is, your concept should be clear. You could take concepts from anywhere, be it notes, books or some youtube videos. Doing topic by topic helps a lot! For that, get topical past papers, they are life-savers! First revise a topic... -
-
Chemistry: Post your doubts here!
oh my god! so wrong :p thank u for pointing out, I'll edit -
Chemistry: Post your doubts here!
equation for the decomposition of CaNO3 is: Ca(NO3)2 >>> 2CaO + 4NO2 +O2 solid residue is CaO Since there are 4.1 g of calcium nitrate: Mr of Ca(NO3)2=164 no. of mol of 4.1 g of calcium nitrate = 4.1/164 =0.025 mol 1 mol of Ca(NO3)2... -
Chemistry: Post your doubts here!
wow!! U did it so cool! I get it...thanks a lot! -
-
Chemistry: Post your doubts here!
totally stuck...no idea how to do this :( help!! -
-
Chemistry: Post your doubts here!
It's KCN that undergoes nucleophilic substitution with halogenalkanes to form propanenitrile which is then reduced with H2SO4 to form propanoic acid. HCN, on the other hand, only reacts with aldehydes and ketones. It's not used in reactions with halogenalkanes -