Post on 03-Jan-2016
transcript
Chapter 20
The Dissolving Process
Part 1
Solutions
• Solutions are homogeneous mixtures.
Solutes and SolventsSolutes and Solvents• “solute” is what is being dissolved.• “solvent” is what it is dissolved in.
• If we make tea and mix sugar into it. The sugar and tea are the solutes. Water is the solvent. The sweet tea is the solution.
Solvation
• Solvation is the process of solvent particles attaching with particles of a solute. As solute dissolves in a solvent the solute particles spread out and become surrounded by solvent particles.
• If water is the solvent we call this process hydration.
Water
• The universal solvent.
Air
• Air is a homogeneous mixture of gases.• Air is a solution of gases.
What is the solvent in air?
• The solvent is the major component in a solution.• All lesser components are solutes.
Dissociation is a process in which ionic compounds separate or split into ions.
Miscibility
• Liquids that are soluble in each other in all proportions are miscible.
• Liquids can also be partially miscible or immiscible.
Like Dissolves Like
• like dissolves like" is an expression used by chemists to remember how some solvents work.
• It refers to "polar" and "nonpolar" solvents and solutes.
Water – Cooking Oil – Food Coloring.
• Water is Polar.
• What are the polarities of cooking oil and food coloring?
Cooking Oil is nonpolar. Food Coloring is polar.
Red Blood Cells
Crescent or sickle-shaped red blood cells (RBCs) are present with Sickle cell anemia, and stand out
clearly against the normal round RBCs.
Some solute-solvent combinations are: example (solute state-solvent state)• oxygen in nitrogen (gas-gas) = air• carbon dioxide in water (gas-liquid) = soda pop• water vapor in air (liquid-gas) = humidity• alcohol in water (liquid-liquid) = liquor• mercury in silver (liquid-solid) = dental amalgam• sugar in water (solid-liquid) = kool-aid• tin in copper (solid-solid) = bronze alloy• How many other combinations are possible?
Homework
• Worksheet: The Dissolving Process