AP Chem Semester Review

Mass Spectrometry separates isotopes of an element to determine __________.

isotopic composition.

The process of __________ involves high-energy electrons ionizing atoms.

Mass Spectrometry

In Mass Spectrometry, ions are separated by their __________ using an electric field.

mass-to-charge ratio (m/z)

The __________ displays isotopic deflection and abundance in Mass Spectrometry.

mass spectrum.

In electron configurations, each orbital can hold __________ electrons with opposite spins.

2

According to the Aufbau principle, electrons fill __________ first.

lower energy orbitals

Coulomb's Law states that the attractive force (F) is proportional to the __________ of particles divided by the square of the distance between them.

charge

Effective Nuclear Charge (Z_eff) is calculated as: Z_eff = __________.

Protons - Core Electrons

Atomic radius decreases across a __________ due to higher nuclear charge.

period

Ionization energy increases across a period and __________ down a group.

decreases

Ionic bonds involve the __________ of electrons between a metal and a nonmetal.

transfer

Hydrogen bonding occurs with H bonded to __________, O, or F.

N

Boyle’s Law states that pressure is inversely proportional to __________.

volume

The definition of a solute is the substance that is __________.

dissolved

Dilution can be expressed as M1V1 = __________.

M2V2

A combustion reaction involves a hydrocarbon and __________.

O2

At the equivalence point in a titration, the moles of titrant equal the moles of __________.

analyte

Oxidation in redox reactions is defined as the __________ of electrons.

loss

The Beer-Lambert Law relates absorbance (A) to concentration and is expressed as A = __________.

εlc

Explain why elements B and Al deviate from normal ionization energy trends. 


Boron (B) and Aluminum (Al) deviate from normal ionization energy trends because their valence electrons occupy the higher-energy p-orbital, which is further from the nucleus and more shielded by inner electrons, making them easier to remove.This results in lower ionization energies compared to elements in the same group, which have their valence electrons in the s-orbital.

What does PES stand for in the context of chemistry?

PES stands for Photoelectron Spectroscopy, a technique used to study the electronic structure of atoms and molecules by measuring the kinetic energy of electrons emitted from a sample.

What is the primary purpose of Mass Spectrometry?

The primary purpose of Mass Spectrometry is to determine the isotopic composition of an element.

What happens during the ionization process in Mass Spectrometry?

High-energy electrons ionize atoms, creating charged ions.

How does mass-to-charge ratio (m/z) affect the separation of ions in Mass Spectrometry?

Ions are separated based on their mass-to-charge ratio (m/z) using an electric field.

What information can be derived from a mass spectrum?

A mass spectrum displays isotopic deflection and abundance of ions.

What does the empirical formula represent in a compound?

The empirical formula represents the smallest whole number ratio of atoms in a compound.

What is the difference between empirical and molecular formulas?

The empirical formula depicts the simplest ratio of atoms, while the molecular formula indicates the actual number of atoms in a molecule.

What is the first step in determining an empirical formula from percentage composition?

The first step is to convert percentage composition to mass.

How do you calculate the molecular formula from the empirical formula?

To find the molecular formula, divide the molecular mass by the empirical mass.

What does a hydrate formula indicate?

A hydrate formula indicates that the ionic compound contains water molecules in its structure.

How many electrons can each orbital hold in electron configurations?

Each orbital can hold 2 electrons with opposite spins.

What are anions and cations?

Anions are negatively charged ions that gain electrons, while cations are positively charged ions that lose electrons.

How many electrons does an anion gain?

An anion gains one or more electrons, depending on its charge.

How many electrons does a cation lose?

A cation loses one or more electrons, depending on its charge.

Why does the size of an atom increase from top to bottom of the periodic table?

The size of the atom increases due to the addition of electron shells, which increases the distance between the nucleus and outermost electrons.

What is effective nuclear charge (Z_eff) and its effect on atomic size across a period?

Effective nuclear charge (Z_eff) is the net positive charge experienced by an electron in a multi-electron atom. As Z_eff increases across a period, it pulls electrons closer to the nucleus, causing the atomic size to decrease.

What distinguishes groups from periods in the periodic table?

Groups are vertical columns in the periodic table, while periods are horizontal rows.

Why can two elements in the same period belong to different groups?

Two elements in the same period can have different chemical properties due to variations in their electron configurations, particularly in the filling of orbitals.

How does Z_eff affect ionization energy trends?

As effective nuclear charge increases, ionization energy tends to increase, making it harder to remove electrons.

What is electron affinity?

Electron affinity is the amount of energy released when an electron is added to a neutral atom to form a negative ion.

What is the relationship between atomic size and electron affinity?

atomic size goes up > electron affinity goes down

What is electronegativity?

Electronegativity is a measure of an atom's ability to attract and hold onto electrons in a chemical bond.

Whats the relationship between electronegativity and nuclear shielding electrons?

nuclear charge goes up > Electronegativity goes up

A dipole is a difference in electrical charge within a molecule, resulting from one end being slightly positive and the other slightly negative due to differences in __________.

electronegativity.

A dipole influences interactions between molecules and can affect properties like __________ and boiling points.

melting.

Nonpolar bonds occur when electrons are shared __________ and have __ dipole moment.

equally, no

Polar bonds occur when electrons are shared __________ and have __ dipole moment.

unequally, a

What kind of bonding occurs in a polyatomic ion?

covalent

Covalent bonding occurs between a _____ & _____.

nonmetal, nonmetal

______ bonding occurs between a metal & nonmetal.

Ionic

_______ bonding occurs between a metal & metal.

Metallic

In a graph of potential energy vs bond distance what’s indicated by y-axis?

bond strength

In a graph of potential energy vs bond distance what’s indicated by x-axis?

bond length

Name the VSPR & angle

180 & linear

Name the VSPR & angle

trigonal planar & 120

Name the VSPR & angle

angular/bent & 118

Name the VSPR & angle

tetrahedral & 109.5

Name the VSPR & angle

trigonal pyramidal & 107

Name the VSPR & angle

angular or bent & 105

Name the VSPR & angle

trigonal bypyramidal & 90/120

Name the VSPR & angle

seesaw & 88

Name the VSPR & angle

t-shaped & 86

Name the VSPR & angle

linear & 84

Name the VSPR & angle

octahedral & 90/180

Name the VSPR & angle

square pyramidal & 88

Name the VSPR & angle

square planar & 86

Name the VSPR & angle

T-shaped & 84

Name the VSPR & angle

LInear & 82

name 3 covalent solids

BN, SiO2, SiC

What are factors that influence KE?

velocity (temp) & mass

which factors influence speed

KE, mass

what does thermal equilibrium mean?

that temperatures are about to be come the same

what do you do when confused about a size of an element?

refer to whether its anion or cation (cations > positive > smaller) (anions > negative > Bigger)

microwave radiation movement?

rotational

infrared radiation movement?

vibrational

ultraviolet / visible radiation

translational

sublimation

solid > gas

deposition

gas > solid

synthesis

A + B > AB

decomposition

AB > A + B

single replacement

AB + C > AC + B

double replacement

AB + CD > AD + CB

combustion

Cx + Hy + O2 > CO2 + H2O

whats an equivalence point in a titration?

when all the titrant reacts w the analyte

titration base?

analyte

titration reactant you adding

titrant