Chemistry Ii Exam Sem 1

Front 1

Colloid

Back 1

a mixture whose particles are intermediate in size between those of a suspension and a solution (1 – 100 nm)
i. Cloudy when concentrated, clear when dilute
ii. Exhibit Tyndall effect (scattering light)
iii. Exhibit Brownian motion (chaotic movement of particles)

Front 2

Hydrogen bond

Back 2

a relatively strong intermolecular force in which a hydrogen atom that is covalently bonded to a very electronegative atom is also weakly bonded to an unshared electron pair of another electronegative atom in the same molecule or one nearby

Front 3

brownian motion

Back 3

the chaotic movement of colloidal particles, caused by collision with particles of the solvent in which they are dispersed

Front 4

deliquescent

Back 4

a term describing a substance that removes sufficient water from the air to form a solution; the solution formed has a lower vapor pressure than that of the water in the air (remove enough water from air to dissolve)

Front 5

desiccant

Back 5

a hygroscopic substance used as a drying agent (ex. silica gel)

Front 6

effloresce

Back 6

to lose water of hydration; the process occurs when the hydrate has a vapor pressure higher than that of water vapor in the air

Front 7

electrolyte

Back 7

a compound that conducts an electric current in aqueous solution or in the molten state; all ionic compounds are electrolytes, but most covalent (molecular) compounds are not

Front 8

emulsion

Back 8

the colloidal dispersion of one liquid in another
b. Emulsifying agent necessary for forming/maintaining stability
c. Examples:
i. Soap emulsifies oil in water
ii. Egg yolks emulsify oil and vinegar to make mayonnaise

Front 9

hygroscopic

Back 9

a term describing salts and other compounds that remove moisture from the air

Front 10

suspension

Back 10

a mixture form which some of the particles settle out slowly upon standing (particles are greater than 100 nm)

Front 11

tyndall effect

Back 11

scattering of light by particles in a colloid or suspension, which causes a beam of light to become visible

Front 12

hydrate

Back 12

a compound that contains water of hydration (water of hydration – water molecule that are part of a crystal structure); this entire crystalline structure (including water molecules) is called the hydrate

Front 13

miscible

Back 13

describes liquids that dissolve in each other

Front 14

saturated (solution)

Back 14

a solution containing the maximum amount of solute for a given amount of solvent at a constant temperature and pressure; an equilibrium exists between undissolved solute and ions in solution

Front 15

activation energy

Back 15

minimum energy colliding particles must have in order to react

Front 16

Catalyst

Back 16

a substance that increases the rate of reaction by lowering the activation-energy barrier; the catalyst is not used up

Front 17

entropy

Back 17

a measure of the disorder of a system; systems tend to go from a state of order (low entropy) to a state of maximum disorder (high entropy)

Front 18

free energy

Back 18

the energy available to do work (Can be obtained from reactions that actually occur)

Front 19

amphoteric

Back 19

substance that can act as both an acid and a base; water is amphoteric

Front 20

Solution

Back 20

stable, homogeneous mixture, particles are less than 1nm

Front 21

Describe how temperature and pressure can effect the solubility of a solute

Back 21

Increased temperature increases the frequency and force of collisions.
a. For solids dissolved in liquids, solubility usually increases with increasing temp
b. For gases dissolved in liquids, solubility decreases with increasing temp
c. Solubility of gases increases with increased pressure above gas

Front 22

Collision theory

Back 22

Atoms, ions, and molecules can react to form products when they collide, provided that the particles have enough kinetic energy. Particles lacking the necessary kinetic energy to react bounce apart when they collide. Activation energy is the minimum amount of energy particles must have to react.

Front 23

Arrhenius acids

Back 23

compounds that ionize to yield hydrogen ions in aqueous solution

Front 24

Arrhenius bases

Back 24

compounds that ionize to yield hydroxide ions in aqueous solution

Front 25

BL acid

Back 25

hydrogen-ion donor

Front 26

BL base

Back 26

hydrogen-ion acceptor

Front 27

Lewis acid

Back 27

Substance that can accept a pair of electrons to form covalent bond

Front 28

Lewis base

Back 28

Substance that can donate a pair of electrons to form covalent bond

Front 29

Strong/weak acids and bases

Back 29

Strong acids are completely ionized in aqueous solutions. (dissociate completely)
Weak acids ionize only slightly in aqueous solutions.
Strong dissociate completely in water; weak don't