Bio - Mixtures, Acids/Bases

Mixture

two or more substances that do not undergo a chemical reaction

Homogeneous Mixture

(same) uniformly distributed

Heterogeneous mixture

(different) not uniformly distributed

Solution

any homogenous mixture that forms a single phase (liquid, solid, gas)

Solute

dissolved substance (glucose, amino acids, mineral alts, carbon dioxide)

Solvent

dissolved substance can dissolve another substance, universal solvent is water

Suspension

(heterogeneous mixture) particles that settle out due to gravity when left standing (ex: fat droplets in Cytoplasm of a cell)

Colloidal dispersion

(homogeneous mixture) - fine particles are dispersed throughout a substance (ex: biological proteins in Cytoplasm of a cell)

Acids

any substance that releases hydrogen ions (H+) in water; taste sour, burns (orange juice, cola)

Bases

any substance that releases hydroxide ions (OH-) in water; feels slippery, taste bitter (soap, bleach, egg whites, baking soda)

pH Scale

measure of hydrogen ions in a solution (0 - 7 = Acids; 7 - 14 Basic {Alkaline]; 7 = neutral)

Indicator

a substance that changes color when the pH goes above or below a certain value

Indicator: Red litmus paper

acidic - stays red; neutral - stays red; basic - turns blue

Indicator: Blue litmus paper

acidic - turns red ; neutral - stays blue; basic - stays blue

Indicator: Neutral litmus paper

acidic - turns red; neutral - no color change; basic - turns blue

Indicator: pH paper

14 different colors (pH values)

Indicator: Methyl Orange (yellow)

acidic - turns red; neutral & basic - no color change

Indicator: Phenolphthalein

acidic & neutral - no color change; basic - turns pink

Indicator: Red cabbage juice

acidic - turns red or pink; neutral - no change; basic - turns blue, green, yellow

Neutralization reaction

double displacement reaction type (AB + CD = AD + CB); Acid + Base = Salt + Water