Answer:
0.47 M
Explanation:
The concentration of the solution can be calculated using the following equation:

<u>Where:</u>
V: is the volume of the solution = 68.6x10⁻² L
η: is the moles of cobalt (II) sulfate
m: is the mass of cobalt (II) sulfate = 89.94 g
M: is the molar mass of cobalt (II) sulfate = 281.103 g/mol
The concentration of cobalt (II) sulfate is:
We used the molar mass of the cobalt (II) sulfate heptahydrate (281.103 g/mol) since it is one of the most common salts of cobalt.
Therefore, the concentration of a solution of cobalt (II) sulfate is 0.47 M (assuming that the cobalt (II) sulfate is heptahydrate).
I hope it helps you!
Answer:
28.9 g
Explanation:
We know that we will need a balanced equation with masses, moles, and molar masses of the compounds involved.
<em>Gather all the information in one place</em> with molar masses above the formulas and masses below them.
: 159.69 28.01
Fe₂O₃ + 3CO ⟶ 2Fe + 3CO₂
Mass/g: 55.0
1. Use the molar mass of Fe₂O₃ to calculate the moles of Fe₂O₃.

2. Use the molar ratio of CO:Fe₂O₃ to calculate the moles of CO.

3.Use the molar mass of CO to calculate the mass of CO.
Answer:
2.48 mol/L.
Explanation:
- The molarity of the solution can be expressed as <em>the number of moles of solute in 1.0 liter of the solution, </em>(M = n / V).
- It is also can be calculated from the relation:
<em>M = (mass / molar mass) solute x (1000 / V of solution)</em>
The solute is toluene and the solvent is benzene.
mass of toluene (solute) = 57.1 g,
molar mass of toluene (solute) = 92.14 g/mol.
volume of the solution = 250 ml.
∴ M = (mass / molar mass) solute x (1000 / V of solution) = [(57.1 g / 92.14 g/mol) x (1000 / 250 ml)] = 2.48 mol/L.
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