Answer:
Molarity of a solution = 1 mol / L
Explanation:
Given:
Amount of NaOH =20 g
Amount of water = 0.50 l
Find:
Molarity of a solution
Computation:
1 mol of NaOH = 40 g
So,
Moles of NaOH = 20 / 40 g = 0.50 mol NaOH
Molarity of a solution = moles of solute / Liters of solution
Molarity of a solution = 0.50 / 0.50
Molarity of a solution = 1 mol / L
Answer: amount of substance n = cV = 2.0 mol/l x 0.25 l = 0.50 mol
Explanation:
Answer:
77%
1.98/2.57= 0.770428016 = 77%
<span>the molar mass of a compound is the sum of the products of the atomic masses by the number of atoms of the element.
molar mass of Na</span>₂SO₄<span> is - 142 g/mol.
1 mol of </span>Na₂SO₄<span> has a mass of 142 g.
In 1 mol of </span>Na₂SO₄<span> the mass of Na is 23 g/mol x 2 = 46 g.
Mass of Na in 1 mol of </span>Na₂SO₄ is - 46 g
mass of Na in 0.820 mol of Na₂SO₄ - 46 g /1 mol x 0.820 mol = 37.72 g.
mass of Na is 37.72 g
Answer: The molecular mass of this compound is 131 g/mol
Explanation:
Depression in freezing point:
where,
= depression in freezing point = 
= freezing point constant = 
m = molality
i = Van't Hoff factor = 1 (for non-electrolyte)
= mass of solute = 0.49 g
= mass of solvent (cyclohexane) = 20.00 g
= molar mass of solute = ?
Now put all the given values in the above formula, we get:
Therefore, the molar mass of solute is 131 g/mol
