Define the following terms:
Solute
Solvent
Solution
Solute is the thing being dissolved
Solvent is the thing dong the dissolving
A solution is a solute dissolved in a solvent.
What is the formula for Concentration?
(Grams of solute/ volume of solvent) x 100
Is it likely that a sample of aluminum and a sample of carbon would have the same density?
No, individual elements and compounds will have their own unique densities.
What are the two most reliable ways to identify unknown substances?
Density and solubility.
How could you separate a mixture of a solid dissolved in a liquid?
Boil the liquid away, the solid will remain.
Is it likely that a 5gram sample of helium gas would have the same solubility in water as a 5gram sample of chlorine gas?
No. Individual elements and compounds will have their own unique solubility constant.
What is Solubility?
How could you separate a mixture of sand and iron shavings?
Magnet. Iron is magnetic.
Will a 12gram sample or an 8 gram sample of lead have a higher density?
They will both have the same density since they are both lead.
Iron has a density of 7.8g/cm3. An unknown sample of metal has a mass of 66.0grams and a volume of 8.5cm3. Could the unknown sample of metal be iron? How do you know?
Yes. 66/8.5 = 7.8g/cm3 which is the same density as Iron
How could you separate a mixture of ginger and paprika (two red spices)?
You could put them in water. One will dissolve before the other. Once one dissolves, you would strain the solution and you would have the two substances separated.
Can two samples have the same volume and density, and have different masses?
No, to have the same densities with the same volumes, they would have to have the same masses.
The solubility of lithium chloride in water is 68.29g/100ml. An unknown substance forms a saturated solution with 35grams in 65ml of water. Is it possible that the unknown substance is lithium chloride? Explain why or why not.
No. (35/65) x 100 = 53.85g/100ml solubility which is not the same as 68.29g/ml
How could you separate a mixture of a two liquids?
Boil them in a distillation device. One liquid will boil faster than the other.
Will 22grams or 12grams of sodium chloride have a higher melting point?
They will have the same melting point since they are both sodium chloride.
However, the 22 grams may take longer to reach the melting point.