24.05.2017 Views

Chem Notebook COmplete

By: Enmanuel Garrido

By: Enmanuel Garrido

SHOW MORE
SHOW LESS

Create successful ePaper yourself

Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.

Part 1: Mass Percent<br />

Mass percent (also called percent by mass, weight percent, or percent by weight) compares the<br />

mass of the solute to the entire mass of the solution.<br />

Notes:<br />

Part 2: Parts per Million<br />

Parts per million (ppm) is another measure of concentration. It is similar to mass percent. But<br />

mass percent indicates the number of grams of solute per 100 g solution. Parts per million<br />

indicates the number of grams of solute per 1,000,000 g solution. This measure of concentration is<br />

often used to express the concentrations of very dilute solutions.<br />

Notes:<br />

Part 3: Molality<br />

Molality (m) is the ratio of the moles of solute to the kilograms of solvent. Note: this is the first<br />

measure of concentration that is concerned with the mass of the solvent, not the mass of the<br />

solution as a whole.<br />

Notes:<br />

Part 4: Grams per Liter<br />

To express the concentration of a solution in grams per liter, you must know the mass of the solute<br />

and the volume of the solution, not just the volume of the solvent.<br />

Notes:<br />

Suppose you wanted to know what the concentration would be before making the solution. Could that<br />

be done? In order to relate the volume or mass of solvent to the volume of solution, you would have<br />

to know the density of the solution. You will see how solution density can be used to calculate<br />

molarity in the next section.

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!