Question

7. A solution is made by dissolving 0.02500 moles of Ba(OH)2 in enough water to make 750. mL of solution. What is the pH of the resulting solution? What is the pH of a 0.25 M aqueous solution of methylamine hydrochloride, CH3NH3CI? Ks for methylamine CH3N H2 is 4.4 x 104. 8.

Answer 1

[Bacot), moles of volume Balon solution (in of ) O-02500 moles 750 mLk 103 z 10.0333 M) strong base, so dissoclate 2x [Bacon ] 2X 0.0333M 2 0.0667 M Bacon) is 2) Con) ? -2 - completely Balon on dissoclation gives 2014 lons. - The -log Corr t og Co-0667) 21.176 pH a 14-000 - 1.176 2 112.824 pr of resulting solurion as 12-824 Crnt is consugake and of weak base CHANH. Calculate Ka from ky and ko Kaxky z kw Kax 4 4X104 z l-oxioly kar 2.3 x 611 Chant CHNM + at 0.25m S 0-25 (neglect x as a clos) kar Chanh, Cut) Conaut *2-3x16') 2

z) x z Cht) 2 2.4 x 100 m prz - Log Cat) z log (2.4x100m) 25.62]