Discussion in 'Cambridge O Levels' started by mohdumar, Jul 14, 2012.
Thank u for these papers...do u when it may be possible to get the grade thresholds?
When will Pak Studies paper 2 be uploaded
Pakistan Studies paper 2 is missing. Would you please be kind enough to upload it
The following papers are missing...
0500 English papers 12, 21, 22, 31, 33
0450 Business Studies papers 11, 12, 13, 22, 23
0455 Economics papers 13, 21, 22, 23, 32
Can you please upload them..??? Thanks...!
Dude A level chemistry p42 is missing! Kindly upload ASAP!
A-Level ( chemistry) paper42! Thnks
0417 ict paper 2 is missing could u please upload it !!!!!
and also the supporting files of 0417 paper 2 & 3
thank you..may god bless u dr..btw u have general paper 8009( for mauritius)
thanks for sharing
1123/22 and 1123/21 r also nt uploaded.can u plz upload them?? well thanx fr the others
june 2012 paper 42 chemistry A level missing. please upload it.
Chmistry p4 2012, ALEVELS pls upload this ppr if ny1 has it?
Pakistan Studies 'Environment of Pakistan' 2059/1 not uploaded.....!
guys need help!!!
Q1_ Hydrated sodium carbonate has the formula Na2CO3.nH2O. An experiment was performed to determine n, the amount of water of crystallization. A sample of 50.00 g of hydrated sodium carbonate was dissolved in 250 cm3 of water. 20 cm3 of this solution reacted completely with 13.95cm3 of 2.00 mol/dm3 hydrochloric acid.
Na2CO3(aq)+ 2HCl (aq) _______ 2NaCl(aq) +CO2(g)+H2O(l)
a)Calculate the amount of HCl acid reacted.
b). calculate the amount of sodium carbonate in the 20.00 cm3 of the solution used in the reaction.
c). calculate the concentration of sodium carbonate in the sample.
d). Calculate the molar mass of the hydrated sodium carbonate.
e). Calculate the value of n.
Pls tell me the paper it is from... Mayb then I ll b able to answer this...
i dont know because its random...
its IB Diploma question ... my teacher gave it....
Oh God! I thought it was an O level Question....and it Blew my head...! No wonder it is so tough!
a) 1.02g => 0.0279 moles
b) 4g => 0.01395 moles
c) 0.6975 g/dm3
Do you have the answers? These are what I got so far..hope its correct xD!
i got the answers...
thnxs a lot...
i know rite!!!
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