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