Lect. 1-3

Question 1

Mixture

Answer 1

Contains particles or units of more than 1 specific atom or molecule i.e. solutions

Question 2

Democritus

Answer 2

Atoms “atomos”

Question 3

Antoine Lavoisier

Answer 3

Law of conservation of mass

Question 4

Joseph Proust

Answer 4

Law of Definite Proportions: i.e. water is always 88.8% oxygen and 11.2% hydrogen

Question 5

John Dalton

Answer 5

First guy with an atomic theory

Question 6

Dalton’s 4 postulates:

Answer 6

• Each element is composed of tiny particles called atoms
• All atoms of a given element are identical, and all atoms of different elements are different
• Atoms are not created or destroyed in a chemical reaction, they are dissociated, combined, or recombined
• Compounds are formed when atoms of different elements combine with one another. A given compound always contains the same relative numbers and types of atoms

Question 7

J.J. Thompson

Answer 7

Electrons: stream of particles through electric field

Question 8

Earnest Rutherford

Answer 8

Nucleus, gold foil experiment

Question 9

Mass number

Answer 9

Protons+neutrons: upper left hand corner

Question 10

Atomic number

Answer 10

Number of protons: bottom left hand corner

Question 11

Isotopes

Answer 11

Same element, but with different number of neutrons

Question 12

The 2 types of pure samples are…

Answer 12

Elements and compounds

Question 13

Mass Spectrometry

Answer 13

• used to compare masses of isotopes
• atoms from a pure sample of an element are ionized (electrons stripped) and sent through a magnetic field
• isotopes with smaller masses are deflected more

Question 14

Average atomic mass

Answer 14

(Mass#%)+(mass#%)+…

Question 15

Mass %

Answer 15

}[(# of atoms of specific element)(elements atomic mass)]/(formula weight of compound)}*100

Question 16

Law of Multiple Proportions

Answer 16

2 compounds made of the same 2 elements, the masses of the elements in each compound are small whole number ratios

Question 17

Mass ratio of elements in a pure sample of a compound (constant composition)

Answer 17

The ratio of isotopes of a certain element in any pure sample of a given compound is constant

Question 18

Wavelength, frequency, speed of light formula

Answer 18

c=λν

Question 19

Purple light

Answer 19

High frequency, high energy, small wavelength

Question 20

Red light

Answer 20

Low frequency, low energy, long wavelength

Question 21

Max Planck

Answer 21

Quantum theory

Question 22

Quantum theory

Answer 22

Energy increases and decreases in discreet units: by a full quantum or not at all

Question 23

Quantum theory/Planks constant Equation

Answer 23

E=hv
E-energy per quantum
H-plancks constant
V-frequency

Question 24

Photoelectric effect

Answer 24

• high intensity, low frequency light won’t eject electrons no matter what
• when threshold frequency is met, electrons are ejected immediately
• increasing intensity of light will increase ejection rate, but not velocity
• increasing frequency of light increases velocity of electrons

Question 25

Einsteins theory

Answer 25

- a beam of light is a stream of particles called photons - energy of a photon is related to its frequency by e=hv - the quantum of Planck is a particle(photon) - if the frequency of an electron is below a certain threshold, no electrons are ejected - if the frequency of the photon is at or above a certain threshold, it's energy is transferred to the electron

Question 26

Bohr Model

Answer 26

Forces of attraction between electrons and nucleus result from opposite charges Shells Electrons in shells have quantized energy levels

Question 27

Shielding effect

Answer 27

Electrons further away from nucleus are shielded by closer electrons

Question 28

Coulomb's law

Answer 28

``` Closer to nucleus=stronger attraction F=k(q1q2/d2) F-force of attraction K-constant Q-magnitude of charge associated with a particle - protons or electrons D-distance between charged particles ```

Question 29

First ionization energy

Answer 29

-minimum amount of energy required to remove the outermost, least tightly held electron

Question 30

Shell organization

Answer 30

SPDF

Question 31

Orbital

Answer 31

Graphic representation of the space an electron will occupy 90% of the time

Question 32

Quantum Mechanical Model

Answer 32

Solves the problem of subshells

Question 33

Periodicity

Answer 33

Predictable trends on the table