JEE Main20254 Apr 2025Morning ShiftChemistryIonic EquilibriumActual
The pH of a 0.01 M weak acid HX ( K _ a =4 10⁻¹⁰ ) is found to be 5. Now the acid solution is diluted with excess of water so that the pH of the solution changes to 6. The new concentration of the diluted weak acid is given as x 10⁻⁴ M . The value of x is ________ (nearest integer)
Correct answer
0
Step-by-step solution
aligned & HX _ ( aq) H _ ( aq ) ⁺+ X _ ( aq ) ⁻ K _ a =4 10⁻¹⁰ & 0.01(1- ) 0.01 0.01 Not justified & 0.01 =10⁻⁵ =10⁻³ & ~K _ a =0.01 ^2=10⁻⁸ aligned On dilution let final concentration of HX = c M aligned & Hx _ ( an ) H _ ( aq ) ⁺+ X _ ( an ) ⁻ & C (1- ) C C & C =10⁻⁶...(1) & C ² 1- = K _ a =10⁻⁸...(2) & 10⁻⁶ 1- =10⁻⁸ aligned Data given is inconsistent & contradictory. This should be bonus.