Aieee questions continued..

ya me too thought the same manmay.strangely a was given as the answer.

oh yeah,it was very obvious indeed rickde.but then in that question,the energy due to thermal motion should also refer to the energy on account of vibrational motion shouldnt it?

Q16. Without a doubt the alcohol is the strongest acid. Oxygen is a electronegative group than is C≡C. Methanol's conjugate base is able to accommodate the negative charge better than C≡C does.

translational motion of a molecule is given by 3RT/2 and this holds irrespective of whether the gas is monoatomic or not".

each degree of freedom has 1/2 RT energy associated wit it.....

for translational motion...there r three degrees (x, y, z) irrespective of the nature of molecules of gas.... hence translational energy is 3RT/2.....

the total energies r different as rotational n vibrational degrees r different

Q 16> CH₃OH

i guess u r confused between alc and alkyne ,
consider the conjugate bases , negative charge will be preferred on oxygen that that on carbon , so conj base of methanol is more stable than that of acetylene , hence the reason.

Q 14> dude , most acidic doesnt mean least basic ,

if it was that way , then i could say that acetic acid is a strong base since it is a weak acid, wich aint true

i think HF will be weakest base , since the conjugate acid will be bearing a +ve charge of F, wich is comparitively less preferred than a +ve charge on other halogens

hence it will be least basic

for 20

M(median) = \left\{L+\frac{\frac{N}{2}-c}{f}xh\right\}

where...

L=lower calss limit of the median class

f = frequency of the median class

h = width of the median class

c= cumulative frequency of the class just preceding the median class

N = \sum{f_i}

source=R.SAgarwal class 11 Pg. SP-7

also a discussion on this topic is at http://www.tutornext.com/mean-mode-median-grouped-data/1983
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var = \frac{\sum{x_{i}^{2}}}{n} - x ²

so \frac{\sum{x_{i}^{2}}}{n} = n ( n + 1 ) ( 2n + 1 )6n = (n+1)(2n+1)/6

and x ² = \left( \frac{n(n+1)}{2n}\right)^{2} = (n+1)²/4

so varience of n natural nos. = (n+1)(2n+1)/6 - (n+1)²/4
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to find the variance of suppose a,b and c
first find x=(a+b+c)/3 (i.e the mean of the nos)
then find ((a-x)²+(b-x)²+(c-x)²)/3 which actually variance
now aplly it for natural nos.:)

U=FRT2 where F=degrees of freedom.
For diatomic, F=5
So, U=5RT2=5PV2.... now the answer will come which is (b)

my question is shouldnt the internal energy be 5RT/2?
how can number of moles be equal to 1 here,so that RT=PV???
the mass given is 1 kg.so for n to be equal to 1,the molar mass of the gas has to 1000which is probably not possible!

21) 1 kg of a diatomic gas is at pressure 8*10⁴Nm^-2.density is 4 kg/m³.wats its energy due 2 thermal motion
a)3*10⁴ b)5*10⁴ c)6*10⁴ d)7*10⁴

14) HI is most acidic i.e. least basic

15) d

20.plz tell me the way to find the median for a class without using an ogivehad earlier done so using an ogive.
also how to find variance of n natural nos.
or provide a link on these

For Q.19>
+ ve deviation is shown by (d) bcoz..the H-bonding of methanol is affected after the addition of benzene--->escaping tendency into vapor pahse increases ---> VP increases

for this type of qs..its very confusing to make out the answer....a quick recap of the this part before exam is often need

the ans given is d for 19.
options a,c represent -ve deviation(maximum boiling azeotropes).
is the reason d as H bonding is hindered decreasing interactions between them and thus more of the solvents move in vapour phase??
plz tel me if i am wrong.

ratne hi padhte hain woh,5-6 example hote hain
koi aake bolega usne samjha hai,lekin I bet agar naya kuch aaya toh woh nahi bata sakta isme

16
d

17
d

Reason:In a the formed carbocation would be very unstable
In b it would be stable but less than c and d
In c and d d has more resonance

18 d

ya arka

ya both of u seem right to me.
although ans to 14 is given as HF which shud be wrong i think.

1..d
2.Molecular hydrogen occurs in two isomeric forms, one with its two proton spins aligned parallel (orthohydrogen), the other with its two proton spins aligned antiparallel (parahydrogen)

so d