Answer:
0.33 mol/kg NH₃
Explanation:
Data:
b(NH₃) = 0.33 mol/kg
b(Na₂SO₄) = 0.10 mol/ kg
Calculations:
The formula for the boiling point elevation ΔTb is

i is the van’t Hoff factor — the number of moles of particles you get from a solute.
(a) For NH₃,
The ammonia is a weak electrolyte, so it exists almost entirely as molecules in solution.
1 mol NH₃ ⟶ 1 mol particles
i ≈ 1, and ib = 1 × 0.33 = 0.33 mol particles per kilogram of water
(b) For Na₂SO₄,
Na₂SO₄(aq) ⟶ 2Na⁺(aq) + 2SO₄²⁻(aq)
1 mol Na₂SO₄ ⟶ 3 mol particles
i = 1 and ib = 3 × 0.10 = 0.30 mol particles per kilogram of water
The NH₃ has more moles of particles, so it has the higher boiling point.
Answer:
Explanation:
By Ideal Gas Law, P1*V1 / T1 = P2*V2 / T2
So new pressure = (P1*V1 / T1) / (V2 / T2)
= P1*V1*T2 / T1*V2
= 800*3.6*298 / 250*1.8
= 1907.2 mmHg
Answer:
5.88 x 10⁻⁴Hz
Explanation:
Given parameters:
Wavelength = 510 x 10⁹m
Unknown:
Frequency = ?
Solution:
To solve this expression, we use the equation below:
V = f∧
V is the velocity = 3 x 10⁸m/s
f is the frequency
∧ is the wavelength
3 x 10⁸ = f x 510 x 10⁹
f = 5.88 x 10⁻⁴Hz
In pb (no3)2 there is:
Lead- 1 atom
Oxygen- 6 atoms
Nitrogen- 2
9 atoms in all