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Chemistry P1 Help
- Thread starter flyingcrayons
- Start date
- Messages
- 677
- Reaction score
- 190
- Points
- 53
mz23 said:
q31: Now a radical is actually an atom of a molecule...Chlorine radical is chlorine atom while oxygen radical is an oxygen atom. So Cl * has 7 electrons in its outer shell while O* has 6 electrons in its outer shell...so 17 +8 =25..odd no of electrons..and both will share their one electron to form a single covalent bond...try drawing that...
q32:Since both H2SO4 and HSO4- dissociate to form H+ ions, so H+conc is high...comparatively sulphate ion conc. is low.......and it is not told that all of the HSO4- wuld dissociate into SO42-...so their molar concentrations cannot be equal ...
q39: tertiary and secondary alcohol in 1 and 2 options respecively will dehydrate to give alkenes that will decolourise KMnO4...while carboxylic acid doesn't dehydrate...
- Messages
- 677
- Reaction score
- 190
- Points
- 53
I think section B is easy because you have 3 options and sometimes 'clever guesses' can work...you need to clear out your concepts for section B as more than one correct options are present and at times it is difficult to figure them out.
BTW no time left for concept clearation!!!
Just practice!
BTW no time left for concept clearation!!!
Just practice!
- Messages
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Ab kia poochna chem ka... dil uth gya chem se aftter physics paper 
!
!
- Messages
- 677
- Reaction score
- 190
- Points
- 53
THE SMA said:
q7:the over all enthalphy is 100... and this is only shown by graph A and C....but as reaction is of two steps..so the graph should have two peaks...so C is the answer ...
q8: use this formula..delta H of a reaction = standard enthalpy chnage of products - standard enthapy change of reactants....or otherwise solve it using hess cycle...
q12:NaCl is pure ionic...AlCl3 and SiCl4 have pure covalent bonding so what is left now is B....and since Mg has high polarising power so bonding has some covalent character...
q13: taking Al as the central atom...there are four bonds around it..3 are with H and one with N...so it has tetrahedral shape...
q26: the alcohol must be a tertiary one as it cnt be ozidised...so with carbon as the central atom...it has OH on one side...CH3 , C2H5 and C3H7 on the other sides..in total there wuld be 7 carbon atoms...
q28: the only option is C cos aldehyde is oxidised by KMnO4 and has carbonyl carbon...giving reaction with DNPH...
- Messages
- 677
- Reaction score
- 190
- Points
- 53
kugs said:
Nov07: q35: here barium nitrate would decompose into barium oxide , nitrogen dioxide and oxygen.Mg will react with oxygen to produce MgO...
june08:
q2: 15+30+15=60g
mass of N in 100g = 15/60 x100 =25g
100g contains25g of N
14g contains 14x25/100=3.5g
moles of nitrogen ATOMS = 3.5/(14x2)=0.125
n =cv, c=n/v
= 0.125/5 =0.03
q6 & 27: explained that before..just search out the post
q33: a catalyst increases the rate of forward and backward reaction at consatnt rate and it doesn't effect the enthalphy change...if u draw an exothermic reaction graph both with and without catalyst, u'll note that enthaply change of reaction remains constant!
Nov08:
q2: considering molar ratios, 10cm^3 of CO2 and 20cm^3 of SO2 will be produced..and 30cm^3 of oxygen will be used..leaving behind 20cm^3 of unreacted oxygen..so vol fter burning is 50cm^3......NaOH will absorb CO2 and SO2...so 50 - 20-10=20cm^3
q10: Kp or Kc values are ONLY effected by change in temperature ONLY!!!
- Messages
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- Reaction score
- 190
- Points
- 53
moon said:
q16: CaCo3 would decompose to give Co2 turning lime water milky...and BaCo3 will react with acid to release gas...
q31: The question says it has a graphite like structure...so properties wuld be same..
june06: q31: as the atomic radius increases, orbital overlap decreases so bondlength increases, nuclear charge is not a relevant point here
q33: reaction doesnt occur spontaneously so it has a high activation energy....while Nitrogen triple bond doesnt exist here its a single bond b/w N in hydrazine...
beacon_of_light said:
here why the answer is not B or A in q 16
and q 31 was about the properties of the atoms that are same in a chlorine molecule having a realative molecular mass 72...didnt understand
thnx in advance and i really appreciate ur help....
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hellllo frdz dont ask who i m if i helped u jus say thankss
then answers for may/june 2010 p1 are
1-b
2-c
3-c
4-d
5-a
and for da last questions 31-b
32-a
33-c
34-b
35-a
36-d
37-d
38 39 and 40 A
hope i have helped u bye for noww
then answers for may/june 2010 p1 are
1-b
2-c
3-c
4-d
5-a
and for da last questions 31-b
32-a
33-c
34-b
35-a
36-d
37-d
38 39 and 40 A
hope i have helped u bye for noww
Need an explaination to this question:
At a total pressure of 1.0 atm dinitrogen tetraoxide is 50% dissociated at a temperature of 60 degrees celcius according to the following equation.
N(2)O(4) ---------> (its actually the equilibrium sign) 2N0(2)
What is the value of the equilibrium constant Kp for this reaction at 60 degrees celcius?
The question's from M/J 06 Q 10.
Thanx.
At a total pressure of 1.0 atm dinitrogen tetraoxide is 50% dissociated at a temperature of 60 degrees celcius according to the following equation.
N(2)O(4) ---------> (its actually the equilibrium sign) 2N0(2)
What is the value of the equilibrium constant Kp for this reaction at 60 degrees celcius?
The question's from M/J 06 Q 10.
Thanx.