mindblank 3.0 (1 Viewer)

[medaspirant]

did like tons of these types of questions earlier in hols but lowkey tired rn so like im not understanding how to approach this q. i believe we find the diluted conc then use ka and ice table but not hundred percent sure.
if someone could assist gr8ly appreciated, @aryaadami ur presense is required lol, thx for the help on the other qs btw.

 

[LennonTheLemon]

With these types of questions throw away any of your memorised approaches in easier acid-base calculations and approach it logically. If you think about the theory, when we dilute a solution of acid, it will shift right to the side with more aqueous ions in order to increase the net concentration of ions and minimise the disturbance to equilibrium (according to LCP of course). That's how you know that in your second ICE table that [H3O+] and [NO2-] must increase, and the final concentration can of HNO2 just be calculated with a simple c1v1=c2v2. Since this is a weak acid and ionisation is partial, then we can use the complete information from the first ICE table to find Ka, since, without Ka, this question would be impossible.

PDF below is the worked solution.