Answer:
Explanation:
Molar mass of KF= 39 + 19= 58g/mol
Mass of KF = 109g
Amount = mass/molar mass
Amount = 109/58
Amount = 1.9moles
Answer:
The temperature at 581.2 mL volume was 242.8 K.
Explanation:
Using Charle's law
Given ,
V₁ = 581.2 mL
V₂ = 830.5 mL
T₁ = ?
T₂ = 347 K
Using above equation as:
<u>The temperature at 581.2 mL volume was 242.8 K.</u>
Answer:
204.8g
Explanation:
The number of moles of a substance is related to its mass and molecular mass as follows:
mole (n) = mass (m) ÷ molar mass (MM)
According to this question, 3.50 moles of sodium chloride (NaCl) is added to a food.
Molar mass of NaCl = 23 + 35.5
= 58.5g/mol
Using mole = mass/molar mass
Mass = molar mass × mole
Mass = 58.5g/mol × 3.5mol
Mass = 204.75
Mass = 204.8grams.
Therefore, 204.8grams of NaCl or common salt was added to the food.
Answer:
Explanation:
H₂SO₄ is a strong acid, which means that most of it ionizes in aqueous solution.
Since it is a diprotic acid (two hydrogen ions) its ionization occurs in two steps:
- H₂SO₄ (aq) → H⁺(aq) + HSO₄⁻(aq)
- HSO₄⁻ (aq) → H⁺(aq) + SO₄²⁻(aq)
Thus, almost all H₂SO₄ has ionized and its final concentration is almost nothing.
After the first ionization, the conentrations of H⁺(aq) and HSO₄⁻ are equal but by the second ionization more H⁺ ions are produced along with SO₄⁻.
You can show it as one step dissociation, assuming 100% dissociation (given this is a strong acid):
By the stequiometry you can build this table:
H₂SO₄ (aq) → 2H⁺(aq) + SO₄²⁻(aq)
Initial A 0 0
Change - x +2x +x
Equilibrium A - x 2x x
As explained, A - x is very low, and 2x is twice x. Thus,
The rank of the concentrations from highest to lowest is:
