AP Chem go crazy

light spectrum

Radio, Micro, Infrared, Visible, UV, X-Ray, Gamma

Wavelength+Frequency Relationship

Inverse

Frequency+Energy Relationship

Direct

Wavelength+Energy Relationship

Inverse

Microwave Effect

Rotate

Infrared Effect

Vibrate

Visible Effect

Electrons jump but fall back down

UV Effect

Bonds Broken

X-Ray

Electrons leave

How to calculate average amu

Multiply mass and percent abundance of isotope, then add all together

J to KJ

1 KJ= 1000 J OR

Binding energy

Energy to remove an electron

How does BE affect CFA?

Bigger binding energy means stronger CFA

How does magnitude of charge affect CFA

Directly

How does distance between charges affect CFA

Inversely

Zeff definition+how to find

Effective number of protons

total #protons-#shielded electrons

Order of Predicting (PS4)

1)Distance

2)Magnitude of Charge

3)Penetration

4)Electron Repulsion

Penetration of Sublevels

Ability of an electron to approach the nucleus

from most to least it’s (s,p,d,f)

Electron Repulsion

How much they repulse from the nucleus

2p³ is less repulsive than 2p⁴

Atomic Radius+CFA

Inverse

AR decreases as you move to the right and increases as you move down

Electronegativity

Direct

EN increases to the right and decreases down

Electron Affinity- definition, effect on CFA and periodic table trend

Energy released when an electron stolen

Direct- greater ea=stronger cfa

increases to right, decreases down

Ionization Energy

direct

increases to right

decreases down

Successive Ionization Energy

Energy to remove electron after electron

The big jump (which can indicate atom) happens when all valence electrons are gone

How to determine strength of ionic bonds (PS5)

1)Distance between cations and anions (so bigger atomic radii=less CFA)

2)Magnitude of Charge (multiply charge of the ions)

Are cations or anions bigger?

cations

What is lattice energy and how does it relate to bond strength?

The amount of energy released when a compound is formed (negative #)

More lattice energy released (absolute value) =stronger bond

Bond Energy

the energy needed to break a bond between atoms

How to predict bond strength

1)bond order

2)bond length

How to find bond length and energy on a potential energy diagram?

lowest point on graph

(bond length, bond energy)

What makes metallic bonds special?

their valence electrons flow freely- called a sea of electrons

Bond order

single bond, double bond, triple bond—the more bonds, the more BE

Bond length

the smaller an atom, the shorter the length— stronger bond!

NASL

Needed-Available=Shared (number of bonds)

Shared-Available÷2=Lone Pair

Which element goes in the center of a lewis structure?

the most electronegative

Which elements need less than 8 electrons?

Hydrogen:2

Boron:6

Isomer

Has the same chemical formula but different lewis structures

Geometric Isomers

Same chemical formula and arrangement, but different 3D shape because of pi bonds

Resonance

when an extra bond can be put anywhere on a compound

Formal charge and how/when to use

to draw a lewis structure

ve⁻-sticks (bonds)-dots(lone electrons)

choose the structure that gets down to zero-if none, choose the most electronegative

pi bonds

the second bond in a double bond

sigma bonds

single bonds on a structure

ex: O-O=O → the bond between the leftmost oxygens is a sigma and one of the bonds on the rightmost oxygens is a sigma

are sigma or pi bonds stronger?

Sigma bonds are typically stronger because they are made when the atoms first interact and pi bonds are made later in the process

How many sigma and pi bonds does a triple bond have?

1 sigma and 2 pi

How to tell somethings hybridization?

The number of electron domains something has

3 domains=sp² and so on

remember that lone pairs also count as a domain!

Where are ion-dipole forces present?

between ion and POLAR molecules!

Are ion-dipole or dipole-dipole forces stronger?

Ion-Dipole because they contain the whole charges of the ion and create a more permanent bond.

Are interactions between polar or nonpolar greater?

Polar because the interactions occur in addition to LDFs

Is CH polar or nonpolar?

nonpolar!

IMF between two ions

ion-ion (ionic)

IMF between an ion and a polar

Ion-Dipole

IMF between Ion and nonpolar

ion induced dipole

polar to nonpolar

dipole induced dipole

H-Bond

hydogen to N, O, or F

Polar to Polar

Dipole-dipole

LDF

nopolar to nonpolar

Melting point of network covalent

High

melting point of metallic

high melting point

When are metallic atoms conductors

as solids

Melting point of group 8

low

melting point of molecular covalent

low

When are molecular covalents polar

in solution

when are molecular covalent nonpolar

as solid

melting point of ionic bonds

medium-high

Network covalent vs molecular covalent

Network are elements and molecular are compounds

Substitutional Alloys

In metallic atoms

similar in size and properties

Interstitial alloys

in metallic atoms

not similar in size; just squeezes in

How are molecular covalent held together

(weak) IMFs

relationship between temperature and pressure

direct

relationship between temperature and volume

direct

relationship between pressure and volume

inverse

relationship between vapor pressure and boiling point

inverse

relationship between temperature and vapor pressure

direct (so more particles can escape)

How does phase change occur?

Enough (kinetic) energy is gained to overcome IMFs

Relationship between molar mass of gas and speed

inverse

relationship between temperature and speed

direct (more collisions)

What is the least ideal combination of pressure and temperature of a gase

low temperature and high pressure

What is T in PV=nRT?

Kelvin!!

relationship between molar mass and IMFs and how does it affect ideal-ness?

direct- higher mm and IMF means less ideal

relationship between volume of a container and pressure and how does that affect ideal-ness?

Inverse- higher volume and lower pressure means more ideal

Empirical formula

lowest whole number ratio of a compound (C4H10=C2H5)

Percent Composition in terms of molar mass

percent by mass- molar mass of specific element over molar mass of compound

Relationship between percent composition in pure substances

it is constant

SNAP

sodium (Na), Nitrate (NO3), Ammonia (NH3), Potassium

Heat Fusion

Enthalpy!!! (delta h)

Heat Vaporization

Energy needed to go from liquid to gas

Physical Change

change in intermolecular forces and properties

ex: solid to liquid

Chemical Change

breaking or forming a bond; new substance

what happens to the temperature of a pure substance during a phase change?

remains constant

how do the energy absorbed in one direction and released in another size up?

they are equal

How do ionic compounds dissolve?

they seperate into cation and anion

how do covalents dissolve?

they seperate into molecules

What states of matter can be used in Q and K expressions?

Solutions or gas (Kp)! no solids or liquids

When do you use a K expression vs a Q one?

use K at equilibrium

What happens when you add a reactant at equilibrium?

The reaction shifts to the forward direction to encourage more products to be made

What happens when you decrease the reactant at equilibrium?

The rxn will shift reverse direction to form more reactants

What happens when you dilute a reaction at equilibrium?

All the molarities will decrease and the reaction will shift towards the side with the most aqueous things

What happens when you increase pressure (decrease volume)?

Reaction shifts to side with least gas

Add heat to rxn @ equilibrium? How affect K?

Shifts to the side that will absorb heat. (endo- right, exo-left)

endo, bigger k

exo- smaller k

What happens when you increase concentration?

If conc of reactants up, shift to products (and vice versa)