Question

What is the pH of a solution prepared by dissolving 5.00 g of Ba(OH)2 in 5.00 liters of water. Assume no volume change after BOH)2 added. (MM of Ba(OH)2 - 171 g/mol). pH = 2.23 pH = 12.43 pH = 11.77 pH = 12.07 pH = 10.60 QUESTIONS A solution is prepared by adding 0.10 mole of sodium fluoride, Naf, to 1.00L of water. Which statement about the solution is true? The concentration of fluoride ions and sodium ions in solution will be identical The solution is acidic. The solution is basic The concentration of fluoride ions will be greater than the concentration of sodium ions. The solution is neutral.

Answer 1

masc Give mass of Bal011), = 50g volume of water = 95. Molar mass of Ba(OH), = 191.34 91mol conc. cf. Balom), = marcas mass * Vor (L) mass C IL 1571.3491mol' 5 = 0.0058'M ! Since, Bacolo ve strong base, dissociates completely Son : Bacon) Bayt 20H 0.0058 2X0.0058 S polla - loqCOHJ . = -log C2X0.0058) = pemeran 1.9355 pbe 14-1820 pon = 14-109355 = 12.07. © Given moles Maf- o.lomol volume o water = 1L conc. of 'Naf - 0:10 - 0.10 M. The pH after calculating for NaH is found to be M = 8.04 lie. Both Nat auld f-weil have same couci: The solution is slightly basic not full balič. 90,101) may be correct. 0 Cre) pri NOx 10-9 M HI Solution , HI is smong acid and dissocialis complelety, - HL H+ + 1 conc. of MI = 1x 10-1M+ 1x107m = 10-9 C1 + 100) = 101x10-7 m pH = -log(101x100 cmq Csligevy less than 1) = -2.0043+9 = HOBT H+ + OBY kg = CH+J[ OBY] | [Hoàn] [H+J = Ka [HOBY] . Tobri Now, HUBY 09183 0:183-X H+ + OBY OSO X X Ка - Xxx 0.183-% 2:06x1019 = X 1183-x X = (0:183-X) (2.06X10-9) 2 = 0.377X10-9 – 2.06 X10-9x x?+2.06X10-9-0:377 X1070 109x?+ 206% -0:377=0 [H0] = 1.941 x 10-5. ipMelon CH 77 4.7130 4.71