Chemistry Semester Exam

Chemistry Study

Entropy

Disorder

0th Law of Thermodynamics

If one object is in thermal equilibrium  with two other objects then those objects must be in thermal equilibrium with each other 

1st Law of Thermodynamics

The heat energy lost by one body is gained by another body. Heat is the energy that is transferred between objects when there is a difference in temperature.  Also, energy can be transferred as work.

2nd Law of Thermodyamics

The entropy  of an isolated system increases

3rd Law of Thermodynamics

A system's entropy (disorder) approaches its lowest possible state as the temperature reaches absolute (0 K, or –273.15 °C)

Dalton

Atoms are tiny invisible spheres. Atoms of one element are identical.Atoms of different elements are different. Atoms can mix. (whole # ratios to form compounds)

Thomson

Discovered the electrons using the cathode ray tube.

Rutherford

Discovered that atoms have a dense positive nucleus (protons) and that an atom is mostly empty space. He used the gold foil experiment to discover this.

Bohr

Organized the electrons into rings around the atom (Called energy levels). He also noted that electrons can gain a fixed amount of energy (quantum) and the electrons will jump up to a higher energy level. Electrons will return to a lower energy level and colorful light will be emitted.

Isotopic Notation

top right- charge

top left- mass

bottom left- atomic #

Mass notation

name of element- mass

isotopes

same element with a different # of neutrons- leads to average mass

Wavelength

how long the space between one peak to the other is.

Bigger-smaller

Frequency

how many peaks in one area

smaller-bigger

Energy (Electromagnetic Spectrum)

how much energy it has (relation to frequency)

Smaller-bigger

Dmitri Mendeleev

Atomic Mass organization

Henry Mosley

Organization by atomic # (current periodic table)

Law of Conservation of Matter

matter cannot be created or destroyed, only transferred from one object to another

Groups

Up and down, have the number of valance electrons

Periods

side to side, number of energy levels

Alkali metals

Column 1, very reactive metals, 1 valence electron, form a +1 charge

Alkaline Earth Metals

Column 2, reactive metals, 2 valence electrons, form a +2 charge

Halogens

Column 17, very reactive nonmetals, 7 valence electrons, -1 charge

Noble Gasses

Column 18, non-reactive nonmetals (gases), 8 valence electrons, full octet, 0 charge.

Metals

malleable, ductile, conductive, shiny, high melting+ boiling points

Nonmetals

Low melting and boiling points, brittle, poor conductors

Mettaloids

Mix of metal and metallic

atomic radius

how big is the atom.

more shells (higher period)= bigger

more protons- smaller (higher nuclear charge)

electron affinity

the attraction of the added electron + nucleus

increases left to right bc more electrons means its closer to a full shell (noble gass 0)

up to down decrease because distance from nucleus leads to lower election affinity

 ionization energy

how much energy it take to remove a electron

Ionization energy decreases as you move down the periodic table- (Increase shielding- decrease ionization energy)

Increases as you move left to right (less electrons= easier to get rid of electrons)

effective nuclear charge

nuclear attraction exterted by protons on electrons

increases left to right bc more protons =more nuclear attraction

decreases up to down bc more levels = shielding

electronegativity

how easy is it for it to gain another electron, Noble gasses have none

increases left to right bc more electrons means its closer to a full shell
up to down decrease because distance from nucleus leads to lower election affinity

LDR forces

weakest temporary bond

Dipole-Dipole

stronger two dipoles- permanent partial charge

Ion-Dipole

partial and full charge

Hydrogen Bonds

Strong- high polar bonds between H and F, N or O, type of dipole dipole