Chemistry 1123 checkup 3

the kinetic theory of gas.

1. Gases are composed of independent molecules. The distance between gas molecules is relatively great, and the volume of each molecule is negligible when compared with the volumes of gas. 2. Gas molecules move rapidly, randomly, and constantly in straight-line paths in any direction. 3. Gas molecules frequently collide and change direction. The collisions are completely elastic. 4. Gas molecules so not interact except during collisions. The attractive force between molecules is negligible. 5. The average kinetic energy of the molecules of a gas is directly proportional to the Kelvin temperature of the gas.

surface tension,capillarity

A meniscus is caused by______________and by_____________________

diffraction pattern

A_____________________is formed when high-energy electromagnetic waves bend around a crystal

exists when two opposing chemical or physical changes occur at equal rates in a closed system.

Equilibrium

amorphous

Some substance that are normally crystalline may become _______________if they are rapidly cooled

unlike,like

The pattern of a crystal is caused by the attraction of particles with ________________electic charges and the repulsion of particles with_____________________charges

temperature,cohesion force

The viscosity of a liquid is affected by________________________and caused by ___________________within the liquid

definite melting point

Whether or not a solid has a _______________________determines whether it is crystalline or amorphous

Surface tension

________________________is the property of liquids that makes the surface of a liquid flat and a droplet spherical

Amorphous,Crystalline

________________solids do not have definite melting points,but______________________solids do have definite melting points

crystal

a substance in which the particles are arranged in an orderly, geometric, repeating pattern

viscosity

ability of a liquid to resist flowing

the kelvin scale represents __________ temperature, and its degrees are always expressed as __________ numbers.

absolute and positive

adhesion

attraction between molecules of two substances in contact with each other.

surface tension

cohesive forces in a liquid create a tight layer of the molecules at the surface

meniscus

concave depression on the surface of a liquid

a liquid ________ because its molecules strike its surface with sufficient force and at the proper angle to overcome the forces that hold them in the liquid phase.

evaporates

effusion

gas particles under pressure passing through an orifice

cohesion

molecular force of attraction for other molecules within the substance.

capillarity

movement of a liquid up or down a tube of adhesion

allotrope

one of the different forms of a polymorphous crystalline solid.

x-ray diffraction

process used to examine a crystal structure

unit cell

smallest portion of a crystal that reveals the three dimensional pattern for the entire crystal.

amorphous

solids whose particles have no crystal structure

Graham law of effusion/diffusion

states that, under conditions of equal temperature and pressure, the rate of effusion for a gas is inversely proportional to the square root of its molar mass

polymorphous

substance that occurs in more than one crystal pattern

supercooled liquid

substances that retain certain liquid properties even at temperatures at which they appear to be solid

diffusion

the gradual mixing of two gases due to spontaneous, random motion.

crystal lattice

three dimensional, repeating arrangement of a crystal.