Chapter 7 Flashcards
Most of the elements in nature are _____ when isolated at room temperature.
solids
There are only 2 elements which are ______ at room temperature.
liquids
What are the 2 elements that are liquids at room temperature?
Hg (mercury) and Br (Bromine)
There are several elements which are _____ at room temperature.
gases
What are the elements that are gases at room temperature?
N (nitrogen), O (oxygen), F (Fluoride), Cl (Chloride), H (hydrogen), and all the noble gases
The _______ ______ ______ proposes that all particles making up a substance (atoms, molecules, and/or ions) are in constant random motion at all temperatures above absolute zero Kelvin.
kinetic molecular theory
____ is made up of tiny particles (atoms, molecules, ion) that have definite size and unalterable characteristics.
Matter
______ _____ is energy due to motion of matter.
Kinetic energy
Particles can transfer kinetic energy to on another through _____ _____ - like billiard balls.
elastic collision
______ _____ is stored energy due to position and composition.
Potential energy
______ ______ are attractions and repulsions of charged entities.
Electrostatic interactions
Particles interact with each other via _____ and _____.
attractions and repulsions
______ ______ are collisions where no kinetic energy is lost to the environment. That is, the sum of the kinetic energy of all participants prior to the collision equals the sum of the kinetic energies of all participants after the collision.
Elastic collisions
Particle speed of kinetic energy increases as the _____ is raised.
temperature
Kinetic energy is a ______ _____.
disruptive force
Potential energy is a _____ _____
cohesive force
When the temperature of a system is raised, the _____ _____ of the particles in the system increases.
kinetic energy
What is the mathematical expression of kinetic energy?
1/2mv^2
The ______ component is a squared factor in kinetic energy.
velocity
In the _____ _____ potential energy (cohesive forces) dominates over kinetic energy (disruptive forces).
solid state
Solids are ____ and have ____ ____ because the strong cohesive forces keep the particles in fixed positions.
rigid; fixed volumes
Solids have ____ _____.
high density
With water ___________, solids are usually denser than their corresponding liquid phase.
being a major exception
Due to the compact and orderly packing of particles in a solid, there is virtually no empty space between particles. Consequently, there is hardly any empty space that can be eliminated by increasing the pressure, and solids exhibit a very ____ _____.
low compessibility
Increasing the temperature increase kinetic energy (disruptive force). The particles will increase vibrational motion about their fixed positions.Thus, they will occupt somewhat more space. Consequently, a solid will exhibit a very _____ _____ _____ with increased temperature.
small thermal expansion
In a _____, the particles are randomly packed, but they are relatively close together.
liquid
The ____ _____ is the physical state in which neither force (disruptive, cohesive) dominates.The kinetic energy and the potential energy have similar magnitude and balance each other.
liquid state
Liquids exhibit both _____ and _____.
fluidity and cohesiveness
Liquids will assume any shape of any container that they can fill meaning they have _____________.
indefinite shape and definite volume
The particles in a liquid are packed together in such a way that they essentially touch one another but there is hardly any space between the particles. The high number of particles per unit volume causes liquids to have _____ _____.
high density
As the particles in a liquid are in physical contact, there is not much space in between them that can be eliminated by increasing the pressure on the system. The particles cannot be squeezed closer together, the __________ ___ ______.
compressibility is small
A liquid will exhibit a ____ ____ _____ with increased temperature.
small thermal expansion
In the _____ _____ the disruptive forces (kinetic energy) dominate over the cohesive forces (potential energy).
gaseous state
A sample of gas is totally flexible. It completely occupies any container in which it is placed and escapes into the atmosphere when released. Gases exhibit _____ shape and ______ volume.
indefinite (for both)
Because the particles are so far apart from each other, there is very little mass per unit volume. Therefore, gases have _____ _____.
low density
Gases are really mostly empty space. Consequently, a lot of this space can be eliminated by putting pressure on the system. Gases exhibit _____ ______. If sufficient pressure is applied, gas molecules are forced to com in contact with each other, and the gas liquefies.
large compressibility
When the temperature is increased, more kinetic energy is imported to the gas particles. The particles will have more velocity, resulting in more energetic collisions with the container walls, which will expand somewhat. Hence, the volume increases and gases exhibit ______ ______ ______.
moderate thermal expansion
_______ is a term that describes an exchange or energy. In the case of phase changes, this refers to a change of state that requires the input of heat energy.
Endothermic
Endo means _____ ____!
energy in
______, _______, and ______ are endothermic processes.
melting, evaporation and sublimation
_______ is a term that describes en exchange of energy. In the case of phase changes, this refers to a change of state that results in heat energy being released.
exothermic