Science Buddies: "Ask an Expert"

I have completed the egg float experiment. I don't understand how to calculate the absolute salt content. The amswers I read were very complicated. I have not taken Chemistry yet. Please help.


[Moderator added: https://www.sciencebuddies.org/science- ... background ]

Hi Joshua,

In general, absolute concentration is a ratio of the amount of solute (thing dissolved - in this case, salt) to the amount of solvent (thing doing the dissolving - in this case, water). There are different ways to calculate concentration. The most common way is molarity (M), which is moles of solute / volume of solvent. To calculate moles, you use the molecular weights found in the periodic table. For sodium chloride (NaCl), or table salt, the molar mass is 58.44 g/mol. You can also calculate molality (m), which is grams of solute / volume of solvent. You should easily be able to calculate molality from the grams of salt you used and the volume of water.

Here is another explanation with examples: http://chemistry.about.com/od/lectureno ... ration.htm

I hope this helps. Please post again (in this same thread) if you are still confused or have more questions.

Heather