<u>Given information:</u>
Concentration of NaF = 0.10 M
Ka of HF = 6.8*10⁻⁴
<u>To determine:</u>
pH of 0.1 M NaF
<u>Explanation:</u>
NaF (aq) ↔ Na+ (aq) + F-(aq)
[Na+] = [F-] = 0.10 M
F- will then react with water in the solution as follows:
F- + H2O ↔ HF + OH-
Kb = [OH-][HF]/[F-]
Kw/Ka = [OH-][HF]/[F-]
At equilibrium: [OH-]=[HF] = x and [F-] = 0.1 - x
10⁻¹⁴/6.8*10⁻⁴ = x²/0.1-x
x = [OH-] = 1.21*10⁻⁶ M
pOH = -log[OH-] = -log[1.21*10⁻⁶] = 5.92
pH = 14 - pOH = 14-5.92 = 8.08
Ans: (b)
pH of 0.10 M NaF is 8.08
The factor that determine how water cycles on earth is the forms that water is found in[solid, liquid and gas].
Answer:
mass of Helium = mole of Helium x Molarmass of Helium
Explanation:
Mole of Helium = volume of Helium/ 22.4dm^3/mol
= 7.00 x 10^2/22.4
= 31.25mol
Mass of Helium = mole of Helium x Molarmass of Helium
= 31.25mol x 4g/mol
= 125g
Answer:
Robots will be created to allow scientists to use computer programs.
Explanation:
There are some other answers, but this one is more sufficient. :)