Chem first semester final

why is energy of electrons quantanized

Because electrons occupy specific energy levels in an atom and can only exist in discrete states, absorbing or emitting energy in quantized amounts when transitioning between these levels.

Coulombs law

• the closer an electron is to the nucleus, the stronger the attraction and the less potential energy there is. in order to remove an electron from an atom, you must add enough energy to overcome the electrostatic force

electromagnetic radiation

is a form of energy that travels through space as waves and includes visible light, radio waves, and gamma rays, characterized by its wavelength and frequency.

aufbau principle

The aufbau principle states that electrons fill atomic orbitals in order of increasing energy, starting from the lowest energy levels before moving to higher ones.

Pauli exclusion principle

is a quantum mechanical principle that states no two electrons can occupy the same quantum state within a quantum system simultaneously, which means that an atomic orbital can hold a maximum of two electrons with opposite spins.

Hunds rule

Hund's rule states that electrons will occupy degenerate orbitals singly and with the same spin before pairing up. This minimizes electron-electron repulsion and maximizes total spin.

ionic bond properties

Ionic bond properties include high melting and boiling points, electrical conductivity when dissolved in water, and the formation of crystalline structures.

Metallic bond properties

Metallic bond properties include good electrical conductivity, malleability, ductility, and high melting and boiling points due to the delocalization of electrons.

interstitial alloy

An interstitial alloy is formed when small atoms occupy the spaces (interstices) between the larger metal atoms in a metallic lattice, altering the physical properties of the alloy.

substitutional alloy

A substitutional alloy is formed when atoms of similar sizes replace some of the host metal's atoms in the metallic lattice, resulting in changes to the alloy's properties.

linear

2 bonding groups, 0 lone pairs, 180

trigonal planar

3 bonding groups, 0 lone pairs, 120

Bent

2 bonding groups, 1 lone pair, less than 120

tetrahedral

4 bonding groups, 0 lone pairs, 109.5

trigonal pyramidal

3 bonding groups, 1 lone pair, less than 109.5

bent

2 bonding groups, 1 lone pair, less than 120 degrees

trigonal pyramidal

5 bonding groups, 0 lone pairs, 90 and 120

seesaw

4 bonding groups, 1 lone pair, less than 120 and 90 degrees

T shaped

3 bonding groups, 2 lone pairs, 90

square pyrmaidal

5 bonding groups, 1 lone pair, less than 90 degrees

square planar

4 bonding groups, 2 lone pairs, 90 degrees

polar covalent bond

A type of chemical bond where two atoms share electrons unequally, resulting in a partial positive charge on one atom and a partial negative charge on the other.

dipoles

molecules with positive and negative charges due to unequal electron sharing.

dipole dipole forces

Attractive forces between polar molecules caused by the positive end of one dipole aligning with the negative end of another.

Hydrogen bonds

a strong type of dipole-dipole interaction that occurs when hydrogen is bonded to highly electronegative atoms like oxygen or nitrogen, resulting in significant polarity.

london dispersion forces

weak intermolecular forces arising from temporary dipoles in nonpolar molecules, dependent on the number of electrons present.

Bond strength

the measure of the energy required to break a chemical bond, indicating the stability of the bond.

Stronger IMF’s=

lower vaporization

what is vapor pressure

the pressure exerted by a vapor in equilibrium with its liquid or solid phase at a given temperature.

how do IMF’s impact vapor pressure

Stronger intermolecular forces result in lower vapor pressure, as more energy is needed to overcome these forces for molecules to escape into the vapor phase.

paper chromotography

a technique used to separate mixtures based on the different affinities of compounds for a stationary phase and a mobile phase.

how do you analyze paper chromotogrophy

Measuring distance traveled by each sample to see if it traveled far enough in comparison to the polarity

Kinetic molecular theory

describes the behavior of gases in terms of particles in constant motion, emphasizing that gas properties are a result of their kinetic energy and interactions.

what are the deviations from kinetic molecular theory

-temp is too low

-pressure is too high

-gasses have strong IMF’s

Maxwell Boltzman

Higher temp, higher variation in particles

why does ideal behavior deviate when the temp is too low

At low temperatures, gas particles have less kinetic energy, leading to stronger intermolecular forces and deviations from ideal gas behavior.

why does ideal behavior deviate when pressure is too high

At high pressures, gas particles are forced closer together, increasing the effects of intermolecular forces and leading to deviations from ideal gas behavior.

why does ideal behavior deviate when IMF’s are strong

When intermolecular forces are strong, they significantly affect the behavior of gas particles, leading to deviations from the ideal gas law as particles cannot be treated as point masses and their interactions cannot be ignored.

Bronsted lowry acid

donates a proton

bronsted lowry base

accepts a proton