1.species having highest electron affinity:
a)O b)F- c)Cl- d)O-
ans given O,shudnt it be O-?
adding more..
2.if a+3b+2c=12,then max value of 6bc(1+a)+a(3b+2c) is
a)112 b)115 c)102 d)92
71yes, First one will be O.
Higher Electron affinity means more tendency to accept electrons. However, F- , Cl - both have complete octet, so they will be neglected completely.
Now for O- and O , O- having 1 deficiency of e- when compared to O which is 2 e deficient will possess less Electron Affinity.
hence O is the answer.
1vivek,O- has the same configuration as that of F.
then how can O have more EA than O-?
also say among S- and S which has greater EA?
shouldnt the answer be S- as it has same configuration as Cl or should it be S?
106O- already has an extra negative charge than a neutral atom. So due to this extra negative charge it will repel any additional charge, hence its electron affinity reduces.
2.if a+3b+2c=12,then max value of 6bc(1+a)+a(3b+2c) is
a)112 b)115 c)102 d)92
6bc + 3ab + 2ac + 6abc = 6abc(1/a + 1/2c + 1/3b + 1)
= 31a+13b+ 12c ≥ (a + 3b + 2c)/3
=> 1a+13b+ 12c ≤ 9/12
also, a + 3b + 2c ≥ 3*3√6abc
=> 6abc ≤ 64
So, max. value = 64 (3/4 + 1) = 16*7 = 112
71O- has the same configuration as that of F.
F is not there in the option.
And you don't compare S- with Cl because both don't have same effective nuclear charge. That should also be taken into the account.
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plz ans these:
1.which isnt true for ideal gas:
(multi correct)
a)it cant be converted to liquid
b)there's no intermolecular attraction
c)all molecules move with same speed
d)at const temp,PV is proportional to amt of gas
c has to bve right but is any other option correct?
2. No of pairs of(x,y) satisfying sin x +sin y=sin(x+y) and |x|+|y|=1 is ...
12. No of pairs of(x,y) satisfying sin x +sin y=sin(x+y) and |x|+|y|=1 is ...
answer is 6
u need take intersection of
x=0;y=0;x+y=0
with the square |x|+|y|=1
262on solving sin x +siny = sin(x+y) ,
we get sin(x/2 - y/2)=0.
therefore, x-y=0 , x/2-y/2=pi, x/2-y/2=2pi.
solving this with |x| +|y| =1 , we get 2 solns. for each.... hence total solns are 2*3 =6.