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What is the concentration in molarity of a solution which is 11.39 %m/v octane (MM = 114.2 g/mol ) in hexane (MM = 86.18 g/mol)?

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Final answer:

To calculate the concentration in molarity of the solution, convert the given %m/v to grams and divide by the molar mass of octane. Then, use the number of moles and volume of solution to calculate the molarity.

Step-by-step explanation:

To calculate the concentration in molarity (M), we need to convert the given %m/v to grams and then divide by the molar mass of octane.

First, calculate the mass of octane in the solution:

Mass of octane = %m/v * volume of solution * density of solution

Mass of octane = 11.39 g/100 mL * volume of solution * density of hexane

Then, use the mass of octane and molar mass to calculate the number of moles of octane:

Moles of octane = Mass of octane / molar mass of octane

Finally, use the number of moles of octane and volume of solution to calculate the concentration in molarity:

Concentration (M) = Moles of octane / volume of solution (in L)

User Fabian Horlacher
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4 votes

Final answer:

To calculate the molarity of the octane solution in hexane, we need to determine the mass of octane, the volume of hexane, and the molar mass of octane. First, we calculate the mass of octane using the percentage by mass and the molar mass. Next, we convert the volume of hexane to liters using its density. Finally, we divide the moles of octane by the volume of hexane to obtain the molarity of the solution.

Step-by-step explanation:

The concentration of a solution is typically expressed in terms of molarity (M). To calculate the molarity of a solution, we need to know the mass of the solute (in this case, octane) and the volume of the solution (in this case, hexane). First, let's calculate the mass of octane using the given percentage by mass and molar mass. Since we know the mass and molar mass, we can calculate the moles of octane. Next, we can calculate the volume of the solution in liters using the density of hexane. Finally, we can use the moles of octane and the volume of the solution to calculate the molarity.

Step 1:Convert the percentage by mass to grams of octane:
11.39% m/v octane = 11.39 g/octane per 100 g solution (since density is given in g/mL

Step 2:Calculate the moles of octane:
moles of octane = (11.39 g/octane) / (114.2 g/mol)

Step 3:Calculate the volume of the solution in liters:

volume of hexane (L) = (100 mL) / (1000 mL/L)

Step 4:Calculate the molarity of the solution:

Molarity (M) = (moles of octane) / (volume of hexane in L)

User Jordan Brough
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