question

1. Mass

answer

amount of matter in a sample
matter = anything that occupies space & has mass
grams, milligrams, kilograms
more mass means more atoms/molecules

question

1. Volume

answer

how much space sometimg takes up
usually liters or milliliters
1 cm³ = 1 mL
measure liquid volume with measuring flask
measure solid volume with displacement
gas volume = volume of container (displacement with container if necessary)

question

1. Density

answer

ratio of mass to volume of an object
each substance has a specific density
d = m/v
density of liquids and solids as a fixed temp is constant
density of gases changes

question

1. Presh

answer

force that gas in a closed container exerts on the container walls
solid/liquid is there, gas exerts presh on walls of environment and everything in it including the solid/liquid
use manometer or barometer to measure (both use Hg)
760 torr = 760 mmHg = 1 atm

question

1. Energy

answer

the ability to do work or transfer heat
heat, light, kinetic, chemical bond energy (different forms)
usually kinetic energy of molecules in chem--greater KE means higher temp and faster movement
breaking bonds takes energy, forming them releases energy
heat is the transfer of KE from one thing to another
1 cal = 4.186 J; 1000 J = 1 kJ
measure it with a calorimeter

question

1. Temperature and Heat

answer

heat is energy flow from high temp thing to low temp thing
temp measures average KE of molecules in a sample
if something increases in temp, that's a heat content increase
substances have different specific heats
K = C + 273; 0 K = -273 C; 0 C = 273 K

question

1. Specific Heat

answer

it's easier to heat some things than others
heat capacity is how much energy something has to absorb for some of it to be raised 1 degree Celsius
specific heat is the heat capacity for 1 g of the substance
q = mst

question

2. Atom

answer

smallest particle of an element
retains the chemical properties of the element

question

2. Parts of an Atom

answer

proton, positive charge
neutron, no charge
nucleons, in the nucleus, protons and neutrons
electrons, negative charge
nucleons have mass; electrons have practically none
neutrons determine the isotope

question

2. Ion

answer

atom with unequal charges inside and outside nucleus
cation, positively charged
anion, negatively charged

question

2. Element

answer

most fundamental unit of matter
can't break it down without losing its identity

question

2. Table Organization

answer

horizontal rows are periods
vertical columns are groups
all elements in the same group have the same number of electrons in outer shells and share properties

question

2. Atomic Number

answer

number of protons in the nucleus of an atom
specific to the element

question

2. Mass Number

answer

protons and neutrons have 1 amu mass
sum of an atom's proton and neutrons is the mass number
isotopes have different numbers of neutrons in their nuclei
doesn't appear on the table because it varies

question

2. Atomic Weight

answer

average mass number, so it's based on each isotope's natural abundance
one for each element
listed on the table

question

3. Molecule

answer

units of two or more atoms
held together with chemical bonds

question

3. Diatomic Molecule

answer

molecule made of just two atoms
some elements exist this way at stp: O₂, I₂, H₂, N₂, Cl₂, F₂, Br₂
Clearly I Have NO Friends, Bro

question

3. Formula Weight

answer

add the atomic weights of all the atoms in the molecule

question

3. Empirical Formula and Molecular Formula

answer

empirical formula is the ratio of atoms within a molecule
the molecular formula divided by the gcf of the subscripts gives the empirical formula

question

3. Percent composition

answer

refers to percent by mass
find it by calculating stuff :P

question

3. Mole

answer

a mole of something is 6.022 x 10²³
the 6 number is called Avogadro's number
a mole of atoms make up the atomic mass

question

3. Mass Composition to Empirical Formula

answer

imagine 100g
convert percents to grams
convert grams to moles
find the ratio between the mole amounts

question

3. Stoichiometry Problems

answer

how much product or reactant is produced or needed in a reaction?
always start with a balanced equation
remember limiting reactants
convert things to moles!

question

3. Entropy

answer

S symbol
If deltaS is negative, reaction loses entropy
If deltaS is positive, reaction gains entropy
Universe tends towards disorder
Low energy states ar emore stable than high energy states
Higher S + Lower E = More Stable

question

3. Enthalpy

answer

term refers to energy states of reactions or products
symbolized with H
decreasing H leads to stability
H decreases: exothermic; H increases: endothermic
endothermic reactions need energy input
energy of products/reactions refers to the energy in the bonds

question

3. Heat of Formation

answer

amount of heat released or absorbed when a mole of a compound is formed
if H_f is negative, then exothermic, and vice versa
for all elements, the heat of formation is zero
heat of formation for entire reaction = sum of product H_fs minus sum of reactant H_fs
Hess's Law

question

3. Hess's Law

answer

If a reaction happens in more than one step, the change in enthalpy for the whole thing is the sum of the changes in enthalpy for each step
Enthalpy is pathway-independent: state function

question

3. Spontaneous Reaction

answer

happens without energy input
can happen for a positive H if S is low enough
can happen for a positive S if H is low enough
spontaneity is determined by Gibbs free energy

question

3. Gibbs Free Energy

answer

ΔG = ΔH - TΔS
T is in Kelvins
determines if a reaction will happen spontaneously or not
if ΔG < 0, then it's spontaneous in that direction
if;;G ; 0, then it's spontaneous in the opposite direction
if ΔG = 0, then there's equilibrium

question

4. Quantum Mechanics

answer

our current theory about how electrons and atoms work
a quantum is a small unit of energy, and all energy is quantized, so all energy exists in multiples of quanta

question

4. Orbitals

answer

electrons exist in them
replaces Bohr model of orbiting
describes the likelihood that an electron will be found in a particular location--a probability function
orbitals have energy shells, shape, subshells
any orbital holds two electrons

question

4. Energy Shell

answer

each orbital is in an energy shell
higher number energy shell
greater energy
farther from nucleus
each energy shell has a whole number

question

4. Orbital Shape and Subshell

answer

4 different shapes that make up subshells
s has 1 orbital
p has 3 orbitals
d has 5 orbitals
f has 7 orbitals

question

4. Heisenberg Principle

answer

it's impossible to know both the position and momentum of an electron at the same time

question

4. Louis De Broglie

answer

matter has the properties of a wave
electrons behave in waves like electromagnetic radiation

question

4. Bohr Model

answer

wrong
electrons orbit the nucleus in true orbits, like how planets orbit the sun

question

4. Aufbau Principle

answer

each subshell is filled before electrons go in the next subshell
Cr and Cu are exceptions (promote a 4s to a 3d)
Hybrid orbitals are exceptions

question

4. Radioactivity

answer

Unstable nucleus undergoes nuclear decay --> radioactive --> releases radioactivity
radioactive particles
alpha
beta
gamma
as a radioactive atom decays
becomes another isotope or
becomes another element

question

4. Geiger Counter

answer

Detects and measures radioactive particles

question

4. Four Types of Radioactive Decay

answer

alpha decay
beta decay
positron emission
gamma decay

question

4. Alpha Decay

answer

emits alpha particle: 2 pros and 2 neus
decreases atomic # by 2 and atomic mass by 4
sometimes symbolized as 4/2He

question

4. Beta Decay

answer

emits a beta particle: one electron
releases an electron from a neutron --> lose neutron and gain proton
atomic # increases by 1 and mass stays the same

question

4. Positron Emission

answer

releases positron: antiparticle of an electron, same magnitude but opposite charge
proton becomes a neutron
decreases atomic # by 1, mass stays the same

question

4. Gamma Decay

answer

emits gamma rays when the atom has too much energy
makes nucleus more stable but doesn't do anything else

question

4. Half-life

answer

rate of a substance's radioactive decay
takes one half-life for half of the substance to decay

question

5. Horizontal and Vertical Similarities

answer

same row (period) --> electrons in same energy shells
same column (group) --> similar chemical and physical properties

question

5. Family Traits

answer

same column
noble gases
alkali metals
alkaline earth metals
halogens

question

5. Alkali Metals

answer

group 1/1A
1 valence electron
very reactive
snihy, grayish-white
melt easily
lower densities than other metals

question

5. Alkaline Earth Metals

answer

group 2/2A
2 valence electrons
less reactive than alkali metals but more reactive than other metals

question

5. The Active Metals

answer

Alkali metals
Alkaline earth metals
they're really reactive...duh

question

5. Halogens

answer

group 17/7A
7 valence electrons
very reactive
look different from each other

question

5. Metals

answer

shiny and conduct heat well
malleable and ductile
all solid at room temp except mercury
lose electrons in bonds

question

5. Nonmetals

answer

share or gain electrons in bonds
poor conductors of heat and electricity
some are solid, liquid, gas at room temp

question

5. Semimetals/Metalloids

answer

some characteristics of metals and nonmentals
can either gain or lose electrons in a bond

question

5. Periodic trends to know

answer

Ionization energy
Electronegativity
Atomic radius
Metallic character

question

5. Atomic Radius

answer

increases towards cesium

question

5. Ionization Energy

answer

energy required to remove an electron from an atom
increases towards fluorine
1st, 2nd, etc.

question

5. Electronegativity

answer

pull that a nucleus exerts on electrons of another atom
increases towards fluorine

question

5. Metallic character

answer

question

5. Lattice Energy

answer

energy required to completely separate a mole of a solid ionic compound into separate ions
higer lattice energy = stronger bond

question

5. Electrostatic Force

answer

attraction betweena positive charge and a negative charge
strong

question

5. Transition Metals

answer

middle of the periodic table
harder than metals
higher melting point than metals
compounds with transition metals are colorful

question

6. Ideal Gas Assumptions

answer

molecules of an ideal gas don't attract or repel each other
molecules of an ideal gas occupy zero volume

question

6. Kinetic Molecular Theory

answer

kinetic energy of a gas molecule increases proportionally with temperature in K

question

6. Network Solid

answer

atoms bonded by covalent bonds in a continuous network
one big macromolecule
no individual molecules
e.g. diamonds or quartz

question

6. Hydrate

answer

Ionic substance where water molecules bond to the ions in a fixed ratio
dot H2O means it's a hydrate
% comp of water by mass in a hydrate is called water of hydration

question

6. Four Types of Crystalline Solids

answer

Ionic
Covalent network
Molecular
Metallic

question

6. Heat of Fusion

answer

amount of heat it takes for a substance to go from solid to liquid

question

6. Heat of Vaporization

answer

Amount of heat it takes for a substance to go from liquid to gas

question

6. Phase change and presh

answer

more pressure means it's harder to get solids to melt or liquids to vaporize
more presssure does the opposite for water--easier to melt

question

6. Triple Point

answer

a particular temperature and pressure
substance can exist as a solid, liquid, or gas

question

6. Vapor Presh

answer

created when liquids below their boiling points evaporate
all liquids in a closed system exert some
higher vapor presh means more volatility
affected by intermolecular forces, temperature, and molecular weight
boiling
all of the presh above a liquid is vapor presh
vapor presh = atmospheric presh

question

6. Energy and Phase Change

answer

solid -----------> gas
low PE --------> high PE, which universe dislikes
low entropy --> high entropy, which universe likes
melting/boiling is spontaneous when the temperature is above the melting/boiling point

question

7. Molarity

answer

M
M = moles of solute/liters of solution

question

7. Molality

answer

m
m = moles of solute/kilograms of solvent

question

7. Solubility Factors

answer

Solids
more soluble at higher temperatures
Gases
less soluble at higher temperatures
more soluble at higher presh
think about carbonated drinks

question

7. Electrolytes

answer

ions in solution
makes the solution about to conduct electricity
the solution is still neutral
in ionic solutions aka elecrolytic solutions

question

7. Solutes and Freezing/Boiling Points

answer

ΔT = kmi
solute effects an increase in boiling point and decrease in freezing point
k changes from solvent to solvent
m = molality
i = the number of particles it dissolves into per mole
sucrose: i = 1
NaCl: i = 2

question

7. Precipitate

answer

solid substance that settles out of a solution
often the result of a double replacement reaction
use solutbility rules

question

7. Solubility Rules

answer

all nitrates and perchlorates are soluble
all alkali metal and ammonium compounds are soluble
hydroxides are insoluble except alkali metals and BaOH
silver, lead, and mercury salts are insoluble except with nitrates and perchlorates

question

8. Kinetics

answer

study of the rates of reactions

question

8. Equilibrium

answer

the point in a chemical reaction at which concentration of reactants and products ceases to change
forward and reverse reaction rates are equal

question

8. Activated Complex/Transition State

answer

unstable
place where products form
need to reach activation energy before activated complex can form

question

8. Factors that affect likelihood of reactions

answer

frequency of collision
concentration of reactants
surface area of reactants
temperature
energy of collision
temperature
nature of reactants
catalysts

question

8. Catalysts

answer

increase rate of reaction by lowering activation energy
not consumed in a reaction
don't change the equilibrium of a reaction

question

8. Equilibrium constant expression

answer

reaction: aA + bB <---> cC + dD
K_eq = ([C]^c [D]^d)/([A]^a [B]^b)
solvents not included
powers are coefficients from the equation
K_eq = products/reactants
if > 1 then forward reaction favored
if < 1 then reverse reaction favored

question

8. Le Chatelier's Principle

answer

add more on one side --> equilibrium shifts to other side
K_eq stays constant unless temperature changes
if stress is placed on a reaction at equilibrium, then the equilibrium will shift in a direction that relieves the stress

question

8. Haber Process

answer

makes ammonia

question

8. Pressure Change Effect on Equilibrium

answer

only applies if some of the things in the reaction are gases
reduce volume --> increase pressure --> equilibrium shifts to side with fewer moles of gas

question

8. Solubility Product Constant

answer

K_sp
Equilibrium constant between insoluble ionic solid and dissolved ions
The values are usually really small
Solids aren't included in normal equilibrium expressions

question

9. Autoionization

answer

spontaneous dissociation of water tha tmakes H+ and OH- ions
reversible
an equilibrium exists between H+, OH-, and H2O
equilibrium expression for it is 10^-14 M² at 25 degrees C
same in every aqueous solution

question

9. pH

answer

"p" means -log
if [H+] = 10^-7 M, then pH = 7

question

9. Different Definitions for Acid and Base

answer

Arrhenius
Acids make H+ in aq
Bases make OH- in aq
Lewis
acids accept electrons in aq
bases donate electrons in aq
Bronsted-Lowry
acids donate protons (H+)
bases accept protons
most common definition currently

question

9. Acid Dissociation Equations

answer

HA(aq) --> H⁺(aq) + A^-(aq)
or
HA(aq) + H₂O(l) --> H₃O⁺(aq) + A^-(aq)

question

9. Base Reaction Equations

answer

A^-(aq) + H⁺(aq) --> HA(aq)
or
A^-(aq) + H₂O(l) --> HA(aq) + OH^-(aq)

question

9. Amphoteric

answer

molecules or ions that can act as acids or bases depending on the solution
most molecules are either acids or bases

question

9. Strong Acids and Bases

answer

completely dissociate
dissociation is 100% irreversible
one-way arrow
pH of 1.0 M strong acid is always 0
pH of 1.0 M strong base is always 14

question

9. List of Strong Acids

answer

HCl
HBr
HI
HNO₃
H₂SO₄ (only the first H is strong)
HClO₄

question

9. List of Strong Bases

answer

LiOH
NaOH
KOH
other group 1 hydroxides

question

9. Weak Acids and Bases

answer

partially and reversibly dissociate
use the reversible arrow
figure out if something's acidic or basic, then it's weak if it isn't on the strong list
remember that pH + pOH = 14 at 25 degrees C

question

9. Conjugate Pairs

answer

molecules that are the same except one has an extra H⁺
the one with the extra H+ is the onjugate acid
the one with fewer H+ is the conjugate base
doesn't necessarily mean that they're an acid and a base
there's an ionic equilibrium between the conjugates
sum of pK_a and pK_b of conjugates always = 14 at 25 C

question

9. Conjugate Rules

answer

Conjugate acid of a strong base is neutral
Conjugate base of a strong acid is neutral
Conjugate acid of a weak base is an acid
Conjugate base of a weak acid is a base

question

9. Buffer

answer

minimize a change in pH when an additional acid or base goes into a solution
a conjugate pair of a weak acid and a weak base so they don't neutralize each other
use Henderson-Hasselbalch equation to calculate pH

question

10. Oxidation States

answer

Sum of oxidation states in a compound is zero
Oxygen: -2
Alkali metals: +1
Alkaline Earth Metals: +2
Halogens: -1
Hydrogen: ±1

question

10. Oxidizing Agent

answer

gets reduced
causes something else to get oxidized

question

10. Reducing Agent

answer

gets oxidized
causes someone else to be reduced

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