Gen Chemistry 1 (complete) Flashcards
A student introduces a particle of unknown identity between two oppositely-charged electrodes and notes that it accelerates toward one of the two electrodes. The particle could be any of the following, EXCEPT a(n):
A) anion B) cation C) neutron D) proton
explain the answer
C neutron
in order for acceleration to happen there needs to be a charge, so the only one that would not have a charge would be a neutron
catalyst is?
any substance that increases reaction rate by decreasing activation energy
covalent bonds are formed between _____
nonmetals; they share electrons
explain what happens to energy when a bond is formed and broken
energy is required when you need to break a bond
energy is released when you need to form a bond
how do reactions caused by collisions work
reactants must collide with enough energy to overcome the activiation energy
reactants must be in the correct spatial orientation
in an anion, what is more; a proton or electron?
electron
ionic bonds are formed between ______
a metal and nonmetal
Keq=
([products]^x)/([reactants]^y)
Metals are (Larger/smaller) atoms with (loosely/tightly) held electrons
Nonmetals are (Larger/smaller) atoms with (loosely/tightly) held electrons
metals are larger atoms with loosely held electrons
nonmetals are smaller atoms with tightly held electrons
Metals form _____. Non metals form ______
cation; anion
Neutron + positron=
proton
Proton + Electron =
neutron
reaction quotient
Q>K, the reaction is left/reactants
Q<K, the reaction is right/products
types of decay
alpha decay
beta decay
electron capture
positron emission
gamma emission
alpha: loss of one He nucleus (z-2)
beta: neutron is changed into proton (z+1)
electron: proton is changed into neutron (z-1)
positron: proton is changed into neutron (SEPARATE FROM BETA DECAY) (neutron + positron)
gamma: the rays are emitted as a byproduct of the types of decay
what do collisions cause
reactions
what is an atom with fewer electrons that protons
cation
what is an isotope and do they have odd or even numbers?
multiple versions of the same atom, but they have a different amount of neutrons; they do not all have odd numbers, but many do
do isotopes have the same number of protons and neutrons
same number of protons but different number of neutrons
what is kinetics
study of reaction rate; aka how quickly the reaction proceeds
what is Le Chatelier’s Principle?
systems already at equilibrium, that experience change, will shift to the left or to the right to reduce the effects of that change and re-establish equilibrium
when it comes to heat of combustion, how does energy play a role in it?
the higher the energy (meaning it is less stable), the higher the heat of combustion
when it comes to size, is a cation bigger or smaller than the neutral counterpart? how about an anion?
Cations are smaller than their neutral counterpart and anions are larger than their neutral counterpart.
on the periodic table, how does electronegativity work? how about size
everything goes to F for electronegativity (the more right and up you, the higher the electronegativity)
the opposite for size (the more right and up you, the smaller the size)
what is the equation for the maximum number of electron in terms of n
how about the equation for maximum number of electrons in subshell
n=2n^2
4/+2
what is the work function
KE= E- ⌀
KE= kinetic energy of the electron
E= energy put into system (energy of photon)
⌀= energy required to release an electron from a metal surface (energy needed to eject a valence e-)
what is kinetic energy in terms of chemistry
excess energy of the system
bonding orbitals vs anti-bonding orbitals (in terms of energy and electron attractive or repulsion)
bonding: lower energy; electrons are in-phase and attractive
anti-bonding: higher energy; electrons are out of phase and repulsive
which are stronger: covalent or ionic?
covalent
what are electrolytes
ions that dissolve in solution that allow the solution to conduct electricity
what are considered good candidates for electrolytes?
strong acids/bases and compounds with a high ionic character make good electrolytes
ionic character
a measure of of the polarity between 2 atoms bonded together
what is condosity
concentration of a sodium chloride solution that would conduct electricity exactly as well as the solution in question
what is bond energy
average energy needed to break all the chemical bonds between two types of atoms in a molecule
what is the difference between bond energy and bond dissociation energy
bond energy is energy contained within the bonds while the other is energy required to break bonds
what is the equation of percent mass
(mass of target element/total molecular mass)x100
molecular formula vs empirical formula
molecular: formula showing the atoms of a molecule. ex. C2H4O2
empirical: formula showing the most simplified form of a molecule. ex. C2H4O2—> CH2O
formula of hydroxide
-OH
formula of nitrate
NO3-
formula of nitrite
NO2-
formula of chlorate
ClO3-
formula of chlorite
ClO2-
formula of hypochlorite
ClO-
formula of perchlorate
ClO4-
formula of carbonate
CO3-
formula of bicarbonate
HCO3-
formula of ammonium
NH4+
formula of sulfate
SO2 2-
formula of phosphate
PO4 3-
formula of manganite
MnO(OH)
formula of permanganate
KMnO4-
formula of cyanide
CN-
single displacement formula
AB+C <=> A+BC
double displacement formula
AB+CD<=>AC+BD
combination formula
A+B <=> AB
decomposition formula
AB<=>A+B
how do you find the limiting reagent
convert everything to moles. make sure the equation is balanced, then the reagent with the smallest molar amount is the limiting reagent
what is the theoretical yield
amount of product that would be created under ideal conditions
what is the actual yield
amount of product actually create. it can be less than theoretical yield due to inefficiencies
what is the percent yield formula
(actual over theoretical)x100
according to Le Chatelier’s, how do you increase the yield
start with more reactants
remove products as they are formed
what is the law of mass action
Keq= [products]^x/[reactants]^y
if Keq > 1, the reaction is (spontaneous/non-spontaneous), which means…
it is spontaneous, which means that at equilibrium there will be more products than reactants
if Keq < 1, the reaction is (spontaneous/non-spontaneous), which means…
it is non-spontaneous, which means that equilibrium there will be more reactants than products
true or false: Keq can only be calculated at equilibrium
true
what is Q
any point or ratio where the products and reactants are not at equilibrium
Q > K means…
think in terms of if the reaction goes right or left
more products than at equilibrium so reaction will go to the left
Q < K means…
think in terms of if the reaction goes right or left
more reactants than at equilibrium so reaction will go the right
what is the difference between kinetics and thermodynamics
in terms of speed and stability
kinetics: speed at which a reaction occurs; does NOT take into account how stable the product is
thermodynamics: stability of reactants and products; does NOT take into account the speed of the reaction
what are two things that need to happen in order for a reaction to occur
- collide with enough energy to overcome the energy of activation
- be in the right spatial orientation
when it comes to rate order graphs, what happens in the 0th order
negative slope; [A] vs time is linear
when it comes to rate order graphs, what happens in the 1st order
negative slope; ln[A] vs time is linear
when it comes to rate order graphs, what happens in the 2nd order
positive slope; 1/[A] vs time is linear
when writing a rate law, what determines the rate
the slow step because when there is a slow step, the speed of the fast step is negligible
fast reactions have (large/small) rate constants
slow reactions have (large/small) rate constants
fast: large
slow: small
what are the units of the 0th order reaction
mol/(LxS)
what are the units of the 1st order reaction
1/s or s^-1
what are the units of 2nd order reaction
L/(mol x s)
