Solutions, Acids, and Bases Ch. 15 and 16. Solution Solute-what is BEING dissolved the lesser substance Solvent-what is DOING the dissolving the greater.

Solutions, Acids, and Bases

Ch. 15 and 16

Solution Solute-what is BEING

dissolved the lesser substance

Solvent-what is DOING the dissolving the greater substance

Solutes and solvents can be any state of matter: solid, liquids or gases

Examples of solutions Solid-solid solution:

Bronze, 18 K gold; pewter

Solid-liquid solution: Saline solution, kool-aid

Liquid-gas solution: Coke

Gas-gas solution: Air

Liquid- liquid solution: Alcohol

Solubility The ability of a

substance to dissolve another substance

You may see this solubility chart on your GHSGT or SAT:

The solubility of which substance is most affected by an increase in temperature?

More surface area (crush)

Shake or stir Increase

temperature Not all substance

dissolve. Some are

Soluble, Insoluble, or partly soluble

To increase RATE of dissolving:

Concentration: the ratio of solute to solvent

Dilute: more solvent than solute (“watered down”)

Concentrated: more solute than solvent (orange juice from

concentrate; Pine Sol)

Concentration of solutions We used solutions of different

concentrations in labs: 1 M HCl; 6 M NaOH; .5 M Pb(NO3)2

The higher the number, the more concentrated the solution

Unit of concentration is Molar (M) 1 Molar solution has 1 mole of solute

dissolved in 1 Liter. 6 Molar solution has 6 moles of solute

dissolved in 1 Liter

Types of solutions Saturated-As much solute as possible is

dissolved at that temperature. Kool-aid, chocolate milk

Unsaturated-More solute can still dissolve in the solution.

Supersaturated- a solution that has dissolved more solute than usual by increasing the temperature. Making jello; or making candy. (You have to

heat the water first to dissolve the sugar.)

Solubility Curve Be able to read

a graph! Saturated is on

the line. Unsaturated is

under the line Supersaturated

is above the line.

Supersaturated

Saturated

Unsaturated

Acids and Bases Are measured by the H+ ion

concentration using the pH scale.

pH Scale pH means –log of H+ concentration scale ranges from 0-14; every step away from

seven is a power of ten more acidic or basic 7 is neutral: H+ = OH- concentration

Acids Produce H+ ions in solution: H+ + H2O -> H3O+ (hydronium ion)

Properties of acids: Taste sour Corrosive Conduct electricity Turns litmus paper RED pH of 0 - 6.9 (pH means the

concentration of H+ ions)

Common Acids Strong acids (strong electrolytes)

HCl; HNO3; H2SO4

HF Lemon juice Gastric acid

Weak Acids (weak electrolytes) Vinegar Carbonic acid Citric acids

Bases Produce OH- ions in solution: Properties of bases:

Taste bitter Feels slippery Corrosive Conduct electricity Turns litmus paper BLUE pH of 7.1 - 14

Common Bases Strong bases (strong

electrolytes) Drano NaOH; KOH

Weak Bases (weak electrolytes) Deodorant Ammonia Soaps Shampoos antacids

Neutralization Reactions

Acid + base = forms a salt and water

A base neutralizes an acid and vice versa.

An antacid (TUMS, rolaids) neutralizes stomach acid

Deodorant neutralizes acidic sweat