Aspirin (acetyl salicyclic acid, molar mass 180 g "mol"^(-1)) used as analgesic has pK_(a) value of 2. Two tablets of aspirin eachweighing 90 mg are dissolved in 100 mL of water. The pH of the solution is

Aspirin (acetyl salicyclic acid, molar mass 180 g "mol"^(-1)) used as

1.	Aspirin (acetyl salicyclic acid, molar mass 180 g "mol"^(-1)) used as analgesic has pK_(a) value of 2. Two tablets of aspirin eachweighing 90 mg are dissolved in 100 mL of water. The pH of the solution is
Answer» 0.5 `1.0` `2.0` `4.0` SOLUTION :Aspirin is a weak ACID. Hence, its pH is given by `pH=(1)/(2)[pK_(a)-log c]` Here, `c=2xx0.09 g "in " 100 ML = 1.8 g L^(-1)` `=(1.8)/(180)M=0.01 M` `:. pH=(1)/(2) [2-log 0.01]=(1)/(2)[2-(-2)]=2`