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Grade 11Physical Chemistry

Which of the following is the weakest acid?
A
Phenol (Ka=1.3×1010)
B
Hydrocyanic acid (Ka=4.9×1010)
C
Acetic acid (Ka=1.8×1010)
D
Benzoic acid (Ka=6.5×1010)

Profile image of Krishna Am
5 Years agoGrade 11
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3 Answers

Profile image of Vikas TU
5 Years ago
Dear student 
The weak acid among following is Phenol 
Because it is having least Ka value , among all four. 
So correct option is A. 
Hope this will help 
Good Luck 
Profile image of ankit singh
5 Years ago
please go through the solution 
 solve by askiitians faculty
 ankit singh 

 

A large Ka value indicates a strong acid because it means the acid is largely dissociated into its ions.
A small Ka value means little of the acid dissociates, then it is a weak acid.
 
∴ Phenol is the weakest acid.
 manir bhopal 
 all the best for your futurew endutrewd
Profile image of adilakshmigogada 27
5 Years ago
A large Ka value indicates a strong acid because it means the acid is largely dissociated into its ions.
A small Ka value means little of the acid dissociates, then it is a weak acid.
 
∴ Phenol is the weakest acid.
 manir bhopal 
 all the best for your futurew endutrewd