Question

Part B 0.65 g of sodium hydroxide (NaOH) pellets are dissolved in water to make 7.0 L of solution. What is the pH of this solution? Express the pH numerically to two decimal places. View Available Hint(s) VO A ROO pH = Submit

Answer 1

PART - B: Ас қою — Molanity (M)= น - X1000 M XY Whene, w = weight of substance taken M = Molecular weight of substance I V= Volume of solution in ml. Given - W = 0.65 9 M of NaOH = 40 g/mol V = F L = 7000 ml i Molarity =- -o X1000 Mху 0.65 | 40 x 7000 *1000 = 2.32 x 10-3 M. i concentration of NaOH in 2.32 x 10-3M.

in solution - NaOH lag) + Nat Coa) + 01- (aq) So, from I mose Na DH we can get i mole of on- ion. | [OH-] = concentration of NaOH = 2.32 x 10-3M solution. V The NaOH Solution is a basic We know, the pH of basic solution is - ÞH = 14 - POH = 14 - [- log [om-]] = 14 + dog [on-] = 14 + log (2:32 x10-5) = 14 + (-2.63) = 14 - 2.63 = 11:37 :: pH of NaOH in 11.37. Ami