Test 2: Unit 5 - Unit 8

Boundary

Boundary

________- can be physical or imaginary, permeable or impenetrable to the flow of matter, conducting or insulating to the heat, rigid or flexible.

Bond Theory VSEPR Model

________- Predicts shapes of molecules by assuming that the valence e pairs are arranged as far from one another as possible (to minimize repulsion)

Photoelectric Effect

________- the ejection of electrons from the surface of metals by radiation, no electrons are ejected unless the frequency exceeds some threshold (depends on metal), the kinetic energy increases linearly with frequency but independent of intensity.

Pauli exclusion principle

________- no two electrons can have the smae four quantum number.

Formal Charge

________- used to determine which structure is the most likely.

Frequency

________- the number of wavelengths that pass a fixed point per second.

Aufbau Principle

________- A scheme to build the ground state electron configs of atoms by the "building up "order.

Joule

________ (J)- is the amount of energy needed to move an object by 1m with 1N force.

Q

________= heat (thermal) energy- the energy that flows into or out of a system because of a difference in temperature between the system and its surroundings.

Calorimetry

________ at constant pressure- reactions done in aqueous solution are at constant pressure, the calorimeter is often nested foam cups containing the solution.

Calorie

________ (Cal)- is the amount of energy needed to raise one gram of water by 1°C.

Diffusion

________- transfer of a gas through space over time.

constant T

At ________ and n (Boyles Law)- P and V are inversely proportional so as V decreases, pressure increase.

Octet rule

________- tendency to have 8ei in outer shells (Its 2e- for H2)

O3

Delocalized Bonding: Resonance- can represented by two different Lewis e- dot formulas or pair is shared (________)

State Function

________- only depends on the initial and final conditions not on the process used (E and U are ________)

constant P

At ________ and T (Avogadros law)- V and n are proportional so as volume increases as moles increases.

entire surface

Pressure is a measure of- the total amount of this push (force) exerted by gas molecules hitting the ________ at one instant.

Light

________ has _ and _ interference- constructive and destructive.

Electromagnetic Radiation

________- A type of energy embodied in oscillating electric and magnetic fields traveling through space.

Von der Waals

________- corrects for the nonideal nature of real gases (P + n^2a /v^2) (V- nb)= nRT.

Ms

(________)- two possible spic orientations of electrons residing in a given orbital, each orbital can hold only two electrons whose spins must oppose one another.

Molecular Geometry

________ of an atom with 2 bonding pairs and 0 lone pairs- linear.

Energy

________ stored in the structure of a compound is- potential.

Daltons Law

________- sum of pressures of all different gases in a mixture equals the total pressure Ptot= Pa + Pb + Pc +….

De Broglie

________ predicted that the wavelength of a particle was- inversely proportional to its momentum.

Heisenberg uncertainty principle

________- we can not measure position and momentum with greaat precision simultaneously.

Lewis

________ structures- that allow us to predict many properties of molecules (Electron Dot Structure)

Ml

(________)- distinguishes orbitals in a subshell that have different shapes and orientations in space, each subshell is subdivided into "orbitals "capable of holding a pair of electrons, and each orbital within a given subshell has the same energy.

Electronegativity

________- ability of an atom to draw bonding electrons to itself, increases from lower- left to upper- right corner.

Thermal Equilibrium

________- heat flows from matter with high temperature to matter with low temperature until both objects reach the same temperature.

Paramagnetic Substance

________- weakly attracted by a magnetic field (unpaired)

N

(________)- the "shell number "in which an electron "resides, "the smaller n is the smaller the orbital the lower the energy of the electron.

Diamagnetic Substance

________- not attracted by a magnetic field (paired)

Atomic Radius Trend

________- in a period (row) r decrease with Z increasing, in a group (column) r increases with period number.

Effusion

________- transfer of a gas through a membrane or orifice rate of effusion is proportional to 1 /√ (Mm)

Endothermic Process

________- a chemical reaction or physical change in which heat is absorbed (q> 0), heat transfers from the surroundings to a system.

Boyles Law

________- gases are compressible P1V1= P2V2.

Exothermic Process

________- a chemical reaction or physical change in which heat is evolved (q <0), heat transfers from a system to the surroundings.

Enthalpy

________- the heat absorbed or evolved in a chemical reactions.

Polar Molecule

________ (Dipole)- exhibiting any asymmetry, having a nonzero dipole moment.

Ionization Energy

________- minimum energy needed to remove an electron from an atom (gas state, valence electron easiest to remove)

Dipole Moment

________- a measure of the degree of charge separation in a molecule.

Electron Configuration

________- a particular distribution of electrons among available sub shells.

Electromagnetic spectrum

________- the range of wavelength or frequency of electromagnetic radiation.

Plancks Quantum Theory

________- Energy of atoms and molecules take only discrete quantities.

energy of an electron

The ________ depends on its "residence "in certain orbital- a shell in a certain distance from the center, a subshell in a certain shape, the subshell with an orientation, es spin direction.

Wavelength

________- The distance between any two adjacent identical points.

constant pressure

Change in enthalpy- the heat of reaction at ________.

Ideal gas assumption

________- often intermolecular forces are essentially negligible, size of the molecules can often be ignored.

Properties of a gas (6)

atoms in constant random motion, fills the container it occupies, low density, compressible, mixtures are homogenous, fluid

Ideal gas assumption

often intermolecular forces are essentially negligible, size of the molecules can often be ignored

pressure is a measure of

the total amount of this push (force) exerted by gas molecules hitting the entire surface at one instant

Boyles Law

gases are compressible P1V1 = P2V2

At constant T and n (Boyles Law)

P and V are inversely proportional so as V decreases, pressure increase

Charless Law

Volume of a gas extrapolates to zero at absolution zero Kelvin V1/T1 = V2/T2

At constant P and n (Charless Law)

V and T are proportional so as T increases, V increases

Avogadros Law

Equal volumes of gases contain same number of moles V1/n1 = V2/n2

At constant P and T (Avogadros law)

V and n are proportional so as volume increases as moles increases

Amontonss Law

Pressure of a gas increases as the temperature of the gas increases P1/T1 = P2/T2

At constant V and n (Amontonss Law)

P and T are proportional so as T increase, P increases

Combined Gas Law

PiVi/Ti = PfVf/Tf

STP (standard temperature and pressure)

0 degrees C, 273.15 K, 1atm, 22.4L/mol

Ideal gas constant or molar gas constant or universal gas constant (R=)

0.08206Latm/molK

Molecular Weight Determination

Mm = mRT/RV

Density Determination

D = MmP/RT

Daltons Law

sum of pressures of all different gases in a mixture equals the total pressure Ptot = Pa + Pb + Pc +…

Moles fraction X

a fraction of moles of "A" in the total moles of the mixture Xa = na/ntot = Pa/Ptot

Von der Waals

corrects for the nonideal nature of real gases (P + n^2a/v^2)(V-nb) = nRT

Kinetic-Molecular Theory

the volume of particles is negligible, particles are in constant motion, no inherent attractive or repulsive forces, and the average kinetic energy of particles is proportional to the temperature

Molecular speed (u) equation

u=√(3RT/Mm)

Diffusion

transfer of a gas through space over time

Effusion

transfer of a gas through a membrane or orifice rate of effusion is proportional to 1/√(Mm)

The energy of a system is

its capacity to do work

Work

is done to achieve motion against an opposing force

Work=

(Force)(Distance)

When a system changes energy as a result of a difference in temperature between the system and surroundings is exchanged

heat

Thermal motion

disorderly motion

Exothermic Process

a chemical reaction or physical change in which heat is evolved (q <0), heat transfers from a system to the surroundings

Endothermic Process

a chemical reaction or physical change in which heat is absorbed (q> 0), heat transfers from the surroundings to a system

System

the part we are interested in

Boundary

can be physical or imaginary, permeable or impenetrable to the flow of matter, conducting or insulating to the heat, rigid or flexible

Surroundings

the rest of the universe

Kinetic Energy

energy of motion or energy that is being transferred

Potential Energy

energy that is stored in an object, or energy associated with the composition and position of the object

Internal Energy (U)

the sum of the kinetic and potential energy of the particles making up a substance

Energy stored in the structure of a compound is

potential

Thermal energy is

kinetic (motion of molecules)

Law of Conservation of Energy

Energy can neither be created or destroyed

Joule (J)

is the amount of energy needed to move an object by 1m with 1N force

1J =

1M*n=1kgm^2/s2

Calorie (Cal)

is the amount of energy needed to raise one gram of water by 1°C

1cal

= 4.184J

The internal energy of an isolated system is _ (1st law of thermodynamics)

The internal energy of an isolated system is CONSTANT

State Function

only depends on the initial and final conditions not on the process used (E and U are state functions)

Pressure Volume Work

work based on a change in volume

q=heat (thermal ) energy

the energy that flows into or out of a system because of a difference in temperature between the system and its surroundings

Heat

exchange of thermal energy, occurs when system and surroundings have a difference in temperature, heat flows from matter with high temperature to matter with low temperature until both objects reach the same temperature

Calorimetry

calculation of the amount of heat (q) from temperature change, means by which energy is transferred from a hot body to a colder body when the two are placed in thermal contact

Heat Capacity (C)

the quantity of heat required to raise the temperature by 1°C