GHSGT REVIEW Structure and Properties of Matter
SOLUTIONS
How is matter classified?
• Mixtures– Sugar and water– air
• Compounds– H2O– NaCl
• Elements– H– O
What is a mixture?
• A combination of two or more substances that are NOT chemically combined
What are the two types of mixtures?
• Homogeneous mixtures – well-mixed and the particles CANNOT be distinguished from one another– EX: sugar dissolved in water
• Heterogeneous mixtures – not evenly mixed and the particles CAN be distinguished from each other– EX: dirt and water mixture
What is a solution?
• A homogeneous mixture in which one substance is dissolved in another substance
What are the 2 parts of a solution?
• Solute – what is being dissolved (present in less amounts)
• Solvent – what is doing the dissolving (present in greater amounts)
Pick out the solvent and solute in the following:
10 grams of sugar dissolved in a gallon of water:Solvent ___________ Solute
___________
Air is 78% nitrogen and 21% oxygen:Solvent ___________ Solute
___________
What is solubility?
• The ability of a substance to dissolve in a solvent.
• How would you describe the solubility of bubble gum in water? Zero solubility, does not dissolve at all!
• How would you describe the solubility of sugar in water? High solubility, dissolves very well!
Why is water described as the universal solvent?
• It can dissolve more substances than any other known substance
What is a saturated solution?
• A solution is said to be saturated when it contains the maximum amount of solute that can dissolve in a certain amount of solvent at a certain temperature.
• Is there a limit to how much sugar you can dissolve in a gallon of tea??
What is an unsaturated solution?
• A solution that contains less than the maximum amount of solute that will dissolve in a certain amount of solvent at a certain temperature.
• Would you describe tea that has had a tablespoon of sugar dissolved in it as a saturated solution or an unsaturated solution? Unsaturated
What is solubility curve?
• A graph that shows how the amount of dissolved solute changes with temperature.
What affects the rate at which a solid substance dissolves in a liquid solvent?
• Agitation – stirring increases the rate of dissolving
• Surface area – increasing the surface area increases the rate of dissolving
• Temperature – increasing the temperature increases the rate of dissolving
Vinegar is a solution of two liquids: water and acetic acid. Most vinegar contains 95% water and 5% acetic acid. In vinegar, acetic
acid is:
a. A solventb. A mixturec. An elementd. A solute
Salad dressing often contains vinegar and oil. Shaking a bottle of dressing combines the ingredients, but afterward the vinegar and oil separate. Which term describes
the salad dressing?a. Solutionb. Solutec. Heterogeneous mixtured. Homogeneous mixture