Answer:
2.4 × 10⁻⁴ M
Explanation:
Step 1: Calculate the concentration of Mg²⁺ coming from Mg(NO₃)₂
Mg(NO₃)₂ is a strong electrolyte and the molar ratio of Mg(NO₃)₂ to Mg²⁺ is 1:1. The initial molar concentration of Mg²⁺ is 1/1 × 0.36 M = 0.36 M.
Step 2: Make an ICE chart for the solution of MgF₂
MgF₂(s) ⇄ Mg²⁺(aq) + 2 F⁻(aq)
I 0.36 0
C +S +2S
E 0.36+S 2S
The solubility product constant is:
Ksp = [Mg²⁺] × [F⁻]² = (0.36+S) × (2S)²
Since S <<< 0.36, 0.36+S ≈ 0.36.
Ksp = 0.36 × 4S² = 8.4 × 10⁻⁸
S = 2.4 × 10⁻⁴ M
The answer is 62.00 g/mol.
Solution:
Knowing that the freezing point of water is 0°C, temperature change Δt is
Δt = 0C - (-1.23°C) = 1.23°C
Since the van 't Hoff factor i is essentially 1 for non-electrolytes dissolved in water, we calculate for the number of moles x of the compound dissolved from the equation
Δt = i Kf m
1.23°C = (1) (1.86°C kg mol-1) (x / 0.105 kg)
x = 0.069435 mol
Therefore, the molar mass of the solute is
molar mass = 4.305g / 0.069435mol = 62.00 g/mol
The average kinetic energy of a collection of gas particles depends on the temperature of the gas and nothing else.
Barium fluoride (BaF2) - Also known as Barium(II) fluoride - because it's a combination of two different kinds of ions (binary = two).
Answer:
66.67%
Explanation:
From the given information:
mass of cyclohexane = 2.9949 grams
density of cyclohexane = 0.779 g/mL
Recall that:
Density = mass/volume
∴
Volume = mass/density
So, the volume of cyclohexane = 2.9949 g/ 0.779 g/mL
= 3.8445 mL
Also,
mass of propylbenzene = 1.6575 grams
density of propylbenzene = 0.862 g/mL
Volume of propylbenzene = 1.6575 g/ 0.862 g/mL
= 1.9229 mL
The volume % composition of cyclohexane from the mixture is:
= 66.67%
