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hacker.djdude

the depression in freezing point of water for same amount of acetic acid is greater then chloroacetic acid then dichloroacetic acid why? define Kf & Kb.

2 nd
why does physiorption decrease with increase of temperature.

why is reduction of metal oxide is easier if the metal formed is in liquid sate at temperature of reduction.

chlorine is electron withdrawing group but it is ortho para directing.

hacker.djdude

help me yaar

akhil_o

1st....acetic acid associates in water(polar solvent)...hence no. of particles decreases..
however this association is greatly increased in chloroactic acid and dichloroacetic acid due to high -I effect of Cl...so association increases...and effectiv no of particles is less than in acetic acid...
since m.Kf depends on no of particles,
depression is max for acetic acid, then chloro- then dichloro

hacker.djdude

yes it's right.
dude but where is other ans.

sneha.bagri

physiorption decrease with increase of temperature because its an exothermic reaction

astatine19

in physisorption, the adsorbate is held through weak forces. As temp increases, k.e. Of adsorbate molecules increases nd they are able break free of these weak interactions. Sneha's explanation is also correct.
when a metal is melted, its entropy increases, so the change in entropy upon reduction of oxide also increases (refer ellingham diagram). So delta S increases, and delta G decreases, nd reduction becomes easier

astatine19

for Cl, -I > +R, so it is deactivating. However, its +R effect operates in o and p positions, so a sigma complex there will not be as unstable as it would be in m position i.e. In m position only -I so highly unstable, in o and p position -I and +R so less unstable, even though inductive is dominating.

hacker.djdude

yaar help me out.

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