SPRING FINAL REVIEW

What is the mass number of an atom?

Mass number = number of protons (P) + number of neutrons (N)

What are isotopes?

Atoms of an element with different numbers of neutrons.

What is Avogadro's number?

6.022 x 10^23, which is the number of atoms or molecules in one mole.

PV=nRT

The ideal gas law equation that relates pressure (P), volume (V), number of moles (n), the ideal gas constant (R), and temperature (T).

At STP, what is the volume occupied by one mole of gas?

22.4 L/mol.

Molarity =

Moles / Liters

how do you find the percent composition?

divide the mass of each element/compound by the total molar mass of the substance and multiply by 100.

What is the empirical formula?

The simplest ratio of elements in a compound.

What is the Aufbau principle?

Electrons fill the lowest energy subshells available first.

What does Coulomb's law describe?

The electrostatic force between charged particles, represented by F = kq1q2/(r^2).

What is an ionic bond?

A bond formed when a cation gives up electrons to a nonmetal, resulting in electrostatic attraction.

What is a dipole?

A pair of opposite electric charges separated by distance in polar covalent bonds.

What is a hydrogen bond?

A strong type of dipole-dipole attraction involving hydrogen and highly electronegative atoms like F, O, or N.

What is kinetic molecular theory?

It explains the behavior of gases in terms of particles in motion.

What is Dalton's law of partial pressures?

P(total) = Pa + Pb + Pc + ..., representing the total pressure as the sum of partial pressures.

What reaction occurs during combustion?

A substance containing H and C reacts with O2 to produce CO2 and H2O.

What do you call the process where like dissolves like?

It refers to the principle of solubility where polar solutes dissolve in polar solvents.

What is the role of a solvent in a solution?

The substance that dissolves the solute, present in greater amount.

What does electron affinity measure?

The energy change that occurs when an electron is added to an atom in the gas state.

What is the definition of electronegativity?

The measure of how strongly the nucleus of an atom attracts electrons in a bond.

What is the significance of resonance in molecular structures?

It describes the scenario where a molecule can be represented by two or more valid Lewis structures.

What does VSEPR stand for?

Valence Shell Electron Pair Repulsion, which predicts molecular geometry based on electron pair repulsion.

What is meant by the term 'molecular geometry'?

The three-dimensional arrangement of atoms within a molecule.

What is the difference between ionic and covalent bonds?

Ionic bonds involve the transfer of electrons; covalent bonds involve the sharing of electrons.

What is the relationship between temperature and vapor pressure?

Temperature and vapor pressure are directly proportional.

What is the purpose of paper chromatography?

To separate and identify components in a mixture based on their different polarities.

What causes higher melting and boiling points in substances?

Stronger intermolecular forces (IMFs), such as hydrogen bonds.

What is an acid-base reaction?

A reaction where an acid donates protons (H+) to a base.

What is the definition of an amphoteric substance?

A substance that can act as either an acid or a base.

What is the significance of formal charge in molecular structures?

It helps in determining the most stable Lewis structure by calculating the charge based on the number of valence electrons.

What is the general reaction format for a precipitation reaction?

Aqueous solutions react to form an insoluble salt.

What is the role of a titration in acid-base chemistry?

To determine the concentration of an acid or base through a color change at the endpoint.

What happens in a redox reaction?

There is a transfer of electrons, changing the oxidation states of participating species.

What does the term 'electrostatic force' refer to?

The force between charged particles, often described by Coulomb's law.

What does a photoelectron spectrum represent?

It shows the energy levels of electrons in an atom and the number of electrons present in each level.

What is the ideal gas equation?

PV = nRT, where P is pressure, V is volume, n is number of moles, R is the gas constant, and T is temperature.

What does Beer’s law indicate?

The relationship between absorbance and concentration of a solution.

What is an expanded octet?

The presence of more than 8 electrons around an atom, typically in elements from period 3 or higher.

What does distillation achieve?

It separates mixtures based on differences in boiling points.