How to Calculate the Concentration of a Solution
A solution is a mixture that is homogeneous at the molecular level.
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Transcript
A solution is a mixture that is homogeneous at the molecular level.
That is, the solute, or dissolved particles, is uniformly distributed throughout the solvent, or dispersion medium. To determine how much solute is dissolved in a solvent, calculate its concentration.
Concentration can be calculated and expressed in different ways such as grams per liter, percent composition by mass, and molarity. Let’s practice these calculations using a solution of sodium chloride, or table salt, where 20 grams of sodium chloride is the solute, and 100 milliliters of water is the solvent.
First, let’s find the mass of the solvent by converting volume to mass. Since 1 milliliter of water equals 1 gram of water, then 100 milliliters of water equals 100 grams of water.
Now let’s calculate the mass of the solution by adding the mass of solute, sodium chloride, plus the mass of solvent, water. The mass of the solution is 120 grams--the mass of 20 grams of sodium chloride plus the mass 100 grams of water. To determine concentration in grams per liter, calculate a simple ratio – grams of solute divided by liters of solution.
In your solution, you have 20 grams of sodium chloride solute and 120 milliliters, or 0.12 liters, of solution. So the concentration of sodium chloride in the solution is 167 grams per liter. Percent composition by mass is an expression of the percent mass of each substance in your solution.
This calculation is the mass of the solute divided by the mass of the solution, with the result multiplied by 100.
You know the mass of the solute, sodium chloride, is 20 grams. And the mass of the solution is 120 grams.
Solving the equation gives you a percent composition of mass of sodium chloride solution of 16.67 percent. Probably the most common calculation for concentration of a solution is molarity – the number of moles of solute per liter of solution.
First, 20 grams of sodium chloride is equal to 0.34 mol. The volume of solution 120 milliliters; converted to liters, this is 0.12 liters.
Solving the equation, you get a molarity of 2.83 Molar, which is expressed as 2.83M.
That is, the solute, or dissolved particles, is uniformly distributed throughout the solvent, or dispersion medium. To determine how much solute is dissolved in a solvent, calculate its concentration.
Concentration can be calculated and expressed in different ways such as grams per liter, percent composition by mass, and molarity. Let’s practice these calculations using a solution of sodium chloride, or table salt, where 20 grams of sodium chloride is the solute, and 100 milliliters of water is the solvent.
First, let’s find the mass of the solvent by converting volume to mass. Since 1 milliliter of water equals 1 gram of water, then 100 milliliters of water equals 100 grams of water.
Now let’s calculate the mass of the solution by adding the mass of solute, sodium chloride, plus the mass of solvent, water. The mass of the solution is 120 grams--the mass of 20 grams of sodium chloride plus the mass 100 grams of water. To determine concentration in grams per liter, calculate a simple ratio – grams of solute divided by liters of solution.
In your solution, you have 20 grams of sodium chloride solute and 120 milliliters, or 0.12 liters, of solution. So the concentration of sodium chloride in the solution is 167 grams per liter. Percent composition by mass is an expression of the percent mass of each substance in your solution.
This calculation is the mass of the solute divided by the mass of the solution, with the result multiplied by 100.
You know the mass of the solute, sodium chloride, is 20 grams. And the mass of the solution is 120 grams.
Solving the equation gives you a percent composition of mass of sodium chloride solution of 16.67 percent. Probably the most common calculation for concentration of a solution is molarity – the number of moles of solute per liter of solution.
First, 20 grams of sodium chloride is equal to 0.34 mol. The volume of solution 120 milliliters; converted to liters, this is 0.12 liters.
Solving the equation, you get a molarity of 2.83 Molar, which is expressed as 2.83M.