General Chemistry

Rutherford’s Model of an Atom

The [... Model] states that an atom is mostly empty space, with electrons orbiting a fixed, positively charged nucleus.

Atomic weight is

the weighted average of the masses of an element's isotopes.

In element notation, Z is the [...]

In element notation, A is the [...]

According to the Bohr Model

electrons orbit the nucleus in orbits that have a set size and energy.

The Heisenberg Uncertainty Principle states that

it is impossible to know the momentum and position of an electron simultaneously.

Hunds rule

states that all orbitals must first have one electron before any orbital can obtain a second electron.

Grandma Hund was like, "don't be greedy now kids!"

Pauli Exclusion Principle

states that no two electrons can share the same four identical quantum numbers.

That means, for paired electrons, one must be +1/2 spin and the other -1/2 spin

Avogadro’s Number = [...]

6.022 × 10²³ = 1 mol

Planck’s Constant (h)

h=6.626 × 10^-34

E=hv

proportionality between frequency (v) and energy

Speed of Light (c)

3.0 × 10 ^8 m/s

Paramagnetic materials

are pulled into external magnetic field.pulled into

Contain one or more unpaired electrons with spin ↑

He atom is paramagnetic or diamagnetic

diamagnetic

Li is paramagnetic or diamagnetic

paramagnetic

azimuthal, 3D shape

Quantum number l is the___quantum number and gives the ——- (subshell)of an orbital

m1 , orbital sub type

Quantum number ___ is the magnetic quantum number and gives the ____

ms , electronic spin

Quantum number is the ____quantum number and gives the ___ of the electron

n , principal , energy level , shell number

Quantum number __ is the ____ quantum number and gives the electron ___ or ____

energy level , principal , 2n²

The maximum number of electrons in a single ___ in terms of ___ quantum number = [...]

What is the maximum number of electrons that can be in the second energy level?

2n² = 2(2²) = 8 electrons

subshell, azithum

The maximum number of electrons in a single___in terms of the___quantum number = 4l+2

s 2

p 6

d 10

p 14

free radical, unpaired electron

A/an ____ is an atom or molecule with an

Aufbau principle

.

---

The______states that electrons will fill the lower energy levels before moving to higher energy orbitals.

Give the Arrhenius equation:

K=A x e -Ea/RT

You can use the Arrhenius equation to show the effect of a change of temperature on the rate constant and therefore on the rate of the reaction

k = rate constant

A = frequency factor

E_a = activation energy

R = gas constant

T = temperature in K

K number of molecular collisons per second

A number of molecular collisions per second with proper orientation

e-Ea /RT probability of succesful collisons

absorbed

If an electron moves to a farther orbital a photon is absorbed

f an electron moves to a farther orbital

different masses

Protons and electrons have different masses.

Protons and neutrons same mass

Electrons have smaller mass

Give the equation for the cell potential (electromotive force) of an electrochemical cell

E cell =Eredcathode - Ered anode

Z_eff

is the attractive positive charge of nuclear protons acting on valence electrons.

Give the approximate electronegativity values of H,C,N,O and F

H - 2.0 C-2.5 N-3.0 O-3.5 F-4.0

Ionic bonds

are formed by the complete transfer of valence electron(s) between atoms.

Bond order

refers to the number of bonds between two atoms (single, double, or triple bond).

Higher the bond strenth the shorter the bond H-H 436 C--C 602 C- - -C 835

Coordinate Covalents

bonds are when a single atom provides both bonding electrons.

Covalent bond

is the sharing electrons between two elements

Cations

are ions with a positive charge.

more protons than electrons

Anions

are ions with a negative charge

more electrons than protons

Crystalline lattices

are large, organized arrays of ions.

solid carbon

the greater the number of bonds (bond order)

the higher the bond strength and the shorter the bond.

Hydrogen bonds are most often formed between hydrogen and the following elements

O, N and F.

Non-polar bonds have a △EN that is

less than 0.5.

Polar bonds have a △EN that is between

0.5 and 1.7.

Van der Waals Forces is a general term that includes ——— forces and ——- forces

dipole-dipole and london dispersion forces

Dipole-dipole

forces are attractive forces between the positive end of one polar molecule and the negative end of another polar molecule.

Place in order of strength: Highest frist —-then small last
hydrogen bonds, dipole-dipole forces, and London dispersion forces

Strength Hydrogen Dipole-Dipole London Dispersion

Sigma

bonds are formed by head-on overlapping between atomic orbitals.

Pi

bonds are formed by lateral (side-by-side) overlap of atomic orbitals.

Give the formula for formal charge

Formal Charge

valence electrons − dots − sticks. dots - nonbonding sticks pairs of bonding electrons

The bond angle of an sp hybridized atom is

180

The bond angle of an sp² hybridized atom is

120°

The bond angle of an sp³ hybridized atom is 

109.5°

Bond angles of an sp³d hybridized atom are

90 and 120

The bond angle of an sp³d² hybridized atom is

90°

An H₂O molecule is a bent because 

---

the lone pair of electrons repulse each other and push the H atoms away

Formal Charge

is the charge given to an individual element within a molecule.

Reaction order

is a number that relates the rate of a chemical reaction to the concentrations of the reacting substances

London dispersion

---

forces are temporary attractive forces created when a temporary dipole induces a dipole in a neighboring molecule.

The units for the rate constant of a first order reaction are

1/s

The units for the rate constant of a zeroth order reaction are

M/s

or a first order reaction:

Rate Law: [...]

Integrated Rate Law: [...]

R=k[A]

[A]=[A]0xe^-kt

For a zeroth order reaction:

Rate Law: 

Integrated Rate Law:

R=K

[A]=[A]0 -kt

or a second order reaction:

Rate Law: [...]

Integrated Rate Law: [...]

R=k[A]2

1/[A] =1/[A]0+kt

Electronegativity

measure of how strongly atoms attract electrons.

s

The units for the rate constant of a second order reaction are

1/Ms

In decomposition reactions,

a single reactant breaks down.

A/an hydrolysis

uses water to break the bonds in a molecule.

A/an neutralization reaction

is when an acid and base react to form water and salt

Combustion reactions

are exothermic reactions in which something reacts with oxygen.

the reaction quotient (Q_c)

is a measure of the relative amounts of products and reactants present in a reaction at a given time.

The units for the rate constant of a first order reaction are

1/s

You exclude pure solids and liquids in the reaction quotient and equilibrium constant because

heir effective concentrations stay constant throughout the reaction.

If Q < K_eq, then the reaction will move to the

right

The reaction quotient (Qc)

is a measure of the relative amounts of products and reactants present in a reaction at a given time.

Exclude pure solids and liquids

If ∆G = O, the reaction will b

equilibrium

If ∆G < O, the reaction will be [...].

spontaneous.

Give the formula for the standard entropy of reaction

Srxn = Sf products-Sfreactants

If ∆G > O, the reaction will be

non-spontaneous

Le Châtelier’s Principle 

states that if a stress is applied to a system, then system shifts to relieve that applied stress.

Ionic bonds have a △EN that is

greater than 1.7

The orbital hybridization of an atom with 3 electron groups is

sp²

The orbital hybridization of an atom with 2 electron groups is

sp

Room temperature is approximately

 25°C aka 75°F 

Deposition

is the phase change from gas to solid.

Give the formula for ∆H when using heat of formations

Hrxn=Hproducts - Hreactants

Body temperature is approximately

37°C aka 98.6°F 

Phase changes from solid → liquid → gas are

endothermic.

Give the formula for ∆H when using bond dissociation energies

Hrxn=Hreactants-Hproducts

Enthalpy (H)

is a measure of the potential energy of a system found in intermolecular attractions and chemical bonds.

Gibbs Free Energy

combines enthalpy and entropy into a single value and is used to determine the spontaneity of a reaction

Sublimation

is the phase change from solid to gas.

If a reaction has a negative ∆H and negative ∆S,

then it will be spontaneous at low temperatures

G =H-TS

Give the Gibbs Free Energy equation that uses the equilibrium constant K_eq

Grxn=-RT In(Keq)

Give the Gibbs Free Energy equations that use the reaction quotient Q

Grxn=RTIn (q/Keq)

Grxn=Grxn+RT In (Q)

phase changes from gas → liquid → solid are

exothermic

solution

is a special type of homogeneous mixture composed of two or more substances.

Equilibrium Constant (K_eq)

is the value of the reaction quotient at chemical equilibrium.

solvent

/an [...] is a liquid that dissolves a solid, liquid or gaseous solute