ACS Chemistry Final Exam

the number of protons in a neutral atom will equal the

# of electrons

What is ∆G when +∆H and -∆S and will the reaction occur?

+∆G rxn will never occur

1 L

= 1 dm^3 1000 mL

an analytical technique to determine the concentration of a solute.

Titration

What type of compound is expected to have the largest dipole movement?

a bent compound

The _____ is titrated with the ______

titrand titrant

atomic number =

# of protons

mass number =

# of protons + neutrons

How do you calculate formal charge?

(#of valence electrons) - (nonbonding electrons) - (bonding electrons / 2)

What is the equation for dilution

(moles solute before dilution) = (moles solute after dilution) C1V1 = C2V2

What is ∆G when +∆H and +∆S and will the reaction occur?

+∆G at low temperatures -∆G at high temperatures rxn will occur at high temperatures

What are the Hess Law rules

- If you reverse the direction of a reaction then reverse the sign of ΔH. - If you change the stoichiometry of a reaction (by multiplying all stoichiometric coefficients by some constant value), then multiple ΔH by this same value. - When summing thermochemical equations, species in the reactants and products only cancel out if they are the exact same chemical as the exact same phase of matter.

What is ∆G when -∆H and +∆S and will the reaction occur?

-∆G rxn will occur at any temperature

What is ∆G when -∆H and -∆S and will the reaction occur?

-∆G at low temperatures +∆G at high temperatures wil occur at low temperatures

What does R equal when dealing with Liters atm/ mol K

.082

Classify the following as an element, compound, or mixture. If it is a mixture, decide if it is a homogeneous or heterogeneous mixture. 1 Sugar 2 Spaghetti Sauce 3 Phosphorus

1 compound, not a mixture 2 mixture, heterogenous 3 element

a double bond is made up of

1 sigma 1 pie

An ionic bond is stronger (i.e. the lattice energy is more negative) if:

1) The charge on the individual ions is greater 2) The distance between + and - charge is less (smaller ions)

Assigning Oxidation Numbers Rules (3)

1. all elements in elemental form have an oxidation # of zero 2. For a monotonic ion the oxidation number equals the charge on the ion 3. The sum of the oxidation numbers in a molecule will equal the charge on the molecule

How many calories are in 1 kcal

1000 cal

1 atm = ? kPA?

101.325

Give the ground-state electron configuration of an atom in the second period

1s2 2s1

how many valence electrons does hydrogen have?

2

Lone PAIRS of electrons, lone electrons. know the difference

2 e = 1 pair 2 e = 2 e

a triple bond is made up of

2 pi bonds 1 sigma bond

What makes up an alpha particle?

2 protons and 2 neutrons

α-particles β-particles γ-rays

2+ elementary charge 1- elementary charge uncharged

What is the molar volume of a gas?

22.4 L

How many Joules in 1 calorie

4.184

If a 17.0g of impure Ni+ metal reacts with excess carbon monoxide, CO, forming 6.25 L of Ni(CO)4 gas under standard temperature and pressure conditions, what is the percent by mass of Ni+ in impure nickel metal sample? What do you start the stoich equation?

6.25 L Ni(CO)4

What does R equal when dealing with Liters kPA/mol K (L/mol K)

8.3145

What does R equal when dealing with meters/mol K (m^3/mol)

8.3145

heat + C + CO2 ->equil-> 2CO if pressure is increased but temperature is kept constant, what will be the result?

CO will decrease C and CO2 will increase

Solubility of CO 3-

Carbonate is insoluble EXCEPT with NH4+ and alkali metals (Ammonium, and Group 1 metals)

Which element is represented by X

Chromium

Has two ionizable protons (H2SO4)

Diprotic acid

Define Bond Polarity

Electrons will spend most of their time around the most electronegative atom

What is the equation for Pressure?

Force/Area

Acids increase the concentration of what? Bases increase the concentration of what?

H+ OH-

List the 7 strong acids

HCl - hydrochloric acid HBr - hydrogen bromide HI - hydrogen iodide HClO3 - Chloric acid HClO4 - Perchloric acid HNO3 - Nitric acid H2SO4 - Sulfuric acid

Define Isoelectronic

Having the same amount of electrons

if a reaction is carried out in a series of steps, ΔH for the reaction equals the sum of enthalpy changes for the individual steps.

Hess's Law

Electrons configuration rule that states electrons do not pair until they have to. (put one electrons in each electron domain then pair up)

Hund's rule

Solubility of OH- and O2-

Hydroxide and Peroxide are insoluble except with alkali metals, Ca2+, Sr2+, Ba2+

An atom has a valence shell configuration of 1s1. To which group of elements on the periodic table does it belong?

IA alkali metals

What does it mean when an element has a high electron affinity

It means that it can easily accept electrons to form negative ions

What does it mean when an element has a low ionization energy?

It means that it can easily lose electrons

the energy released when one mole of an ionic solid is formed from gaseous ions. Measures the strength of an ionic bond

Lattice energy

Solubility: C2H3O2

Methyl carbonate is soluble

Temperature in Gas Law equations must be in what type of measurement? What is the conversion?

Must be in Kelvin 273.15 + C = K

What is one weak base you should memorize

NH3 (ammonia)

Solubility: NO3-

Nitrate is soluble

List the shape, electron domain geometry, and predicted bond angle of a molecule with 6 electron domains

Octahedral 90º

List one weakness of the Bohr model

Only orbits of specific radii are permitted for the electron in a hydrogen atom.

Assigning Oxidation Number Rule Exceptions

Oxygen = -2 except in Peroxide = -1 Hydrogen = +1 when with nonmetal -1 when with metal Halogens are -1 except when with Oxygen while Fluorine is ALWAYS -2

Gas Law: Pressure- Temperature relationship, at constant volume. Gay-Lusaacs' Law

P/T = constant

P1V1 will always equal________ if temperature and particle numbers are constant

P2V2

Gas Law: Pressure-Volume relationship, at constant temperature. Boyle's Law

PV = constant

What is the main gas law equation?

PV=nRT (pressure x volume) =

An experimental phenomena associated with atoms having unpaired electrons - which states such substances are attracted to magnetic fields

Paramagnetism

Solubility of PO4 3-

Phosphate is insoluble EXCEPT with NH4+ and alkali metals (Ammonium, and Group 1 metals)

Can be observed without changing the identity & composition of a substance

Physical property (color, density, melting point) all intensive. do not depend on amount of substance e

Describe the atom. What makes up the nucleus and where do electrons reside

Protons and neutrons form the small, dense nucleus; electrons are found in a diffuse cloud around the nucleus; most of the volume of an atom is empty space.

Phrase to remember greatest wavelength/least frequency to smallest wavelength/greatest frequency

Rain Makes Igloos Very Unstable - Xtra Gay radio - microwave - infared - visible - UV - xray - gamma

Who discovered the nucleus by observing the scattering of α-particles off of a thin gold foil & discovered the proton by bombarding N2 with α-particles.

Rutherford

Who discovered the proton?

Rutherford by bombarding N2 with alpha particles

Solubility of Cl- Br- I-

Soluble except in Ag2+, Pb2+, Hg2+

6 electron domains results in what type of hybridization?

Sp3d2

Solubility of SO4 2-

Sulfate is soluble except in Sr2+, Hg2+, Ba2+, Pb2+, Ca2+

Solubility of SO3 2-

Sulfite is insoluble EXCEPT with NH4+ and alkali metals (Ammonium, and Group 1 metals)

Solubility of S 2-

Sulfur is insoluble EXCEPT with NH4+, alkali metals, (Ammonium, Group 1)

Consider this equation at constant temperature and volume 2SO2 (g) + O2 (g) ->equilibrium-> 2SO3 (g) What is the effect of removing some SO3 from a system initially at equilibrium

The concentration of SO2 decreases more than O2

Why are lattice energies listed as positive values instead of negative values?

This represents the energy needed to break apart one mole of substance, rather than the energy released when the substance forms.

Gas Law: Temperature-Volume relationship, at constant pressure. What is the constant for Charle's Law?

V/T = constant

Energy is released when

a bond forms

What does a bonding electron domain represent?

a bond. single or multiple

What does a nonbonding electron domain represent?

a lone PAIR of electrons

What particle, if lost from the nucleus, would NOT cause a change in the atomic number?

a neutron because it has no charge

What do neutralization reactions take place in

acid + base leaving salt + water

two or more different physical forms in which an element can exist. Graphite, charcoal, and diamond are all ________ of carbon.

allotropes

a substance that produces ions when dissolved in solution.

an electrolyte

Identify the bond that would form between an element with a low ionization energy and an element with a high electron affinity

an ionic bond

When resonance structures are shown, the real structure is actually an

average of all of them

when an atom of an electropositive atom becomes an ion it..?

becomes larger

Energy is required to

break a bond

How did Thompson discover the Electron?

by cathode

Which are larger - cations or anions

cations (+)

Cannot be observed without changing the identity & composition of a substance

chemical property

The type of bond that results when both elements contribute electrons but one element furnishes both electrons

coordinate covalent bond

The type of bond that results when both elements contribute electrons to form a shared pair

covalent bonds

a molecule in which a concentration of positive electric charge is separated from a concentration of negative charge.

dipole

High energy photons have enough energy to do what?

disrupt covalent bonds

A solution will conduct electricity if it contains what?

dissolved ions

List the electron domain geometry & molecular geometry of a molecule with 2 electron domains (2 bonding 0 nonbonding)

electron domain geometry: linear molecular geometry: linear

List the electron domain geometry & molecular geometry of a molecule with 6 electron domains (6 bonding 0 nonbonding)

electron domain geometry: octahedral molecular geometry: octahedral ex: SF6

List the electron domain geometry & molecular geometry of a molecule with 6 electron domains (5 bonding 1 nonbonding)

electron domain geometry: octahedral molecular geometry: square pyramidal ex: BrF5

List the electron domain geometry & molecular geometry of a molecule with 4 electron domains (2 bonding 2 nonbonding)

electron domain geometry: tetrahedral molecular geometry: bent/nonlinear ex: H2O

List the electron domain geometry & molecular geometry of a molecule with 4 electron domains (4 bonding 0 nonbonding)

electron domain geometry: tetrahedral molecular geometry: tetrahedral

List the electron domain geometry & molecular geometry of a molecule with 4 electron domains (3 bonding 1 nonbonding)

electron domain geometry: tetrahedral molecular geometry: trigonal pyramidal ex: NH3

List the electron domain geometry & molecular geometry of a molecule with 5 electron domains (2 bonding 3 nonbonding)

electron domain geometry: trigonal bipyramidal molecular geometry: linear ex: I3-

List the electron domain geometry & molecular geometry of a molecule with 5 electron domains (4 bonding 1 nonbonding)

electron domain geometry: trigonal bipyramidal molecular geometry: see saw shape ex: SF4

List the electron domain geometry & molecular geometry of a molecule with 5 electron domains (3 bonding 2 nonbonding)

electron domain geometry: trigonal bipyramidal molecular geometry: t-shaped ex: CIF3

List the electron domain geometry & molecular geometry of a molecule with 5 electron domains (5 bonding 0 nonbonding)

electron domain geometry: trigonal bipyramidal molecular geometry: trigonal bipyramidal ex: PCl5

List the electron domain geometry & molecular geometry of a molecule with 3 electron domains (2 bonding 1nonbonding)

electron domain geometry: trigonal planar molecular geometry: bent

List the electron domain geometry & molecular geometry of a molecule with 3 electron domains (3 bonding 0 nonbonding)

electron domain geometry: trigonal planar molecular geometry: trigonal planar

Electronegativity periodic trend

electronegativity is greater the higher up on the right of the periodic table

δ+ goes over the ____________ and δ- over the ___________ atom

electropositive, electronegative

Properties that do depend on the amount of matter present.

extensive

What does the Oxidizing Agent do in a redox reaction? (aka the oxidant)

gains an electron. Becomes reduced

What does the Reducing Agent do in a redox reaction? (aka the Reductant)

gives away an electron. Becomes oxidized

What does a low vapor pressure value indicate (little tendency to change from liquid to gas)

higher heat of vaporization higher boiling points high surface tension

What is effective nuclear charge and what is its periodic trend

how tightly electrons are held greatest in bottom right.

The boiling point of H2O, compared with other members of the series can be explained by

hydrogen bonding

heat + CaSO3 ->equal-> CaO + SO2 what will cause an increase in pressure when equilibrium is reestablished?

increasing the reaction temperature

Nearly all the mass in an atom is located _________ because both ______ & ______ are located there, and each of these particles have a mass larger than the ______

inside the nucleus protons & neutrons electron

an electronegativity difference ≥ 1.7 indicates an ________ (sometimes you see 2.0 instead of 1.7). An electronegativity difference ≤ 0.5 is generally considered ___________. If it is somewhere in the middle it is considered ________

ionic nonpolar polar

What type of bond has a low conductivity as a solid but a high conductivity when fused?

ionic Ex: NaCl

Bond formed from: metal+nonmetals

ionic bond

Which type of compound has a higher melting point?

ionic compounds have higher melting points that molecular compounds

two or more compounds with the same formula but a different arrangement of atoms in the molecule and different properties

isomer

Forms of the same elements that differ in amount of neutrons

isotopes

What has to be true of a non polar molecule that has polar bonds

it must be symmetric enough so that all the dipoles cancel out

Atomic/ionic radii periodic trend

largest is on the bottom left

List the shape, electron domain geometry, and predicted bond angle of a molecule with 2 electron domains

linear 180º

What does a high vapor pressure value indicate

lower heats of vaporization lower boiling points less surface tension

measure of how much matter an object contains

mass

how to find the correct number of neutrons

mass number - atomic number

What type of element tends to lose electrons

metals

How do you calculate Molarity

mol/L

bond formed from: two nonmetals

molecular compound

What do the 4 quantum numbers stand for?

n = energy level l = (n-1) ml -l to l mn 1/2 or -1/2 (spin)

Which drop in energy level results in the greatest emission of energy?

n=2 to n=1

poor conductors, brittle

nonmetal

What type of element tends to gain electrons

nonmetals

What does an element need to have to be paramagnetic

one or more unpaired electrons

What are rows What are columns

periods are rows groups of columns

What two subatomic particles have the most mass, but occupy very little of the volume of an atom

protons and neutrons

reaction in which electrons are transferred from one reactant to the other

redox reactions

List the quantum numbers for the s, p, d, and f orbitals

s 1,0,0 p 2, 1, -1-0-1 d 3, 2, -2--1-0-1-2 f 4, 3 -3--2--1-0-1-2-3

Define electropositive atoms. Where are they located

smallest value, least electronegative. Located bottom left of periodic table

The strong bases are what?

soluble group 1 group 2 metal hydroxides

The ______ is dissolved in the _______

solute solvent

2 electron domains results in what type of hybridization?

sp

Thompson discovered the Plum Pudding Model - what was that? Who proved him wrong?

stated that nucleus was a scattered positive sphere with electrons embedded in it, was proved wrong by Rutherford who did the gold foil experiment

What does a neutralization reaction occur between? What does it result in?

strong acid + base H2O

contains more dissolved solute than a saturated solution at that temperature.

supersaturated solution

What effects the vapor pressure of a liquid

temperature

List the shape, electron domain geometry, and predicted bond angle of a molecule with 4 electron domains

tetrahedral 109.5º

When alpha particles were shot at a metal foil target, most passed through without deflections, while others deflected at large angles. What did this suggest to Rutherford?

that the atoms of the metal were mostly empty space, while the nucleus consisted of most of the mass which included highly condensed positive particles (which caused the deflection).

What isIonization energy, and what is its periodic trend

the amount of energy required to remove an electron from ground state largest amount energy is top right

The greater the wavelength of a photon..?

the lower its frequency

What did Millikan discover from his oil drop experiments?

the magnitude of the charge on an electron

What is Electron affinity, and what is its periodic trend

the potential energy change when and electron is added to a gaseous atom or ion the more negative, the more energy released most negative at top right

PCl5 ->equilibrium-> PCl3 + Cl2 what will cause an equilibrium shift to the right

the removal of Cl2

equal volumes of gas under the same temperature and pressure will have...?

the same amount of molecules (avagondros)

The greater the frequency of a photon...?

the shorter its wavelength

How does a sodium ion differ from a sodium atom?

the sodium ion has fewer electrons

What is the molecular weight?

the sum of the mass of each element

the numerical value of the equilibrium constant for any chemical change is effected by changing the what

the temperature

List the shape, electron domain geometry, and predicted bond angle of a molecule with 5 electron domains

trigonal bipyramidal, 120º equitorial & 90º axial

List the shape, electron domain geometry, and predicted bond angle of a molecule with 3 electron domains

trigonal planar 120º

contains less dissolved solute than a saturated solution at that temperature

unsaturated solution

measure force of gravity of an object

weight

What is the formula for ∆G?

∆G = ∆H-T∆S