SOLUTIONS, ACID AND BASES

Solutions, Solubility & Concentration

substance being dissolved Solution mixture that has the same composition color, density and taste throughout- the best mixed mixture- A homogeneous mixture. Solute substance being dissolved Solvent substance doing dissolving * Solutions can also be gaseous, like the air you breath, or even solid, like brass and sterling silver. A solution can be found in all three states of matter.

When forming a solution, there are three ways to speed up the rate of the dissolving process:   Stirring brings more solvent in contract w/ solute Increase Surface area by breaking up a solid, for instance, by crushing it into a powder, allows more solvent to come in contract w/ solute Increase temperature increasing temperature speeds up particles causing them to bump each other, breaking apart and coming in contract w/ solvent

percent by volume of solute in solvent Solubility maximum amount of a solute that can be dissolved in a given amount of solvent at a temperature Concentration percent by volume of solute in solvent concentrated – large amount of solute in solvent Ex: Lemonade made with too much solute- super sweet dilute – small amount of solute in solvent Ex: Lemonade made with not enough solute- tastes like water

Types Of Solution Saturated Unsaturated Supersaturated contains all solute it can hold at given temperature able to dissolve more solute at given temperature contains more solute then a saturated one solution is unstable

Acids, Bases and Salts

Acid substance that produces hydrogen ions (H+) in solution Four properties of acids: acids taste sour acids are electrolytes (can conduct electricity in a solution) acids are corrosive acids react with indicators to produce a predictable color change

Base substance that produces hydroxide ions (OH-) in solution; also accepts H+ from acids Five properties of bases:   in undissolved state, many bases are crystalline solid in solution, bases feel slippery bases have a bitter taste strong bases are corrosive bases react with indicators

organic compound that changes color in the presence of acid or base Indicator organic compound that changes color in the presence of acid or base Ex. litmus paper Neutralization chemical reaction between an acid and a base in a water solution which results in formation of salt and water  Salt compound formed when negative ions of an acid combine with positive ions from a base

Strength of Acids and Bases

The strength of an acid or base depends on how many acid or base particles dissociate (change into) into ions in water. Strong acid ionizes almost completely in water Weak acid only partly ionizes in solution Strong base dissociates completely in solution Weak base does not completely dissociate

Dissociate= chemical change Dissolve= physical change * it is possible to have dilute solutions of strong acids and bases, as well as concentrated solutions of weak acids and bases. Strength vs. Concentration The terms strong and weak refer to the ease which an acid or base dissociates in a solution. The terms dilute and concentrated are used to indicate the amount of acid or base dissolved in solution

pH measure of concentration of H+ ions in a solution or how acidic or basic it is pH scale typically ranges from 0 – 14 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 ACIDIC BASIC NEUTRAL STRONG WEAK