Atomic Structure

Question 1

mass number

Answer 1

sum of protons and neutrons

Question 2

protium

Answer 2

1 p 0 n

Question 3

deuterium

Answer 3

1p 1n

Question 4

tritium

Answer 4

1p 2n

Question 5

atomic mass

Answer 5

same as mass number. in amu

Question 6

atomic weight

Answer 6

constant for a given element, reported in periodic table. almost all elements exist as two or more isotopes, usually in same proportions. weighted average. mass of “average” atom of that element, and mass of one mole of the element, in grams.

Question 7

1 amu

Answer 7

1/12 the mass of carbon-12 atom, so amu is approx mass of one p or n

Question 8

mass number

Answer 8

sum of protons and neutrons

Question 9

Avogadro’s number

Answer 9

6.02 x 10^23. a mole is that amount of things. atomic weight of carbon is 12 g/mol, which means average carbon atom has a mass of 12.0 amu, 6.02 x 10^23 carbon atoms have 12 g

Question 10

Rutherford

Answer 10

atom has dense positively charged nucleus

Question 11

Planck

Answer 11

E=hf, energy of a quantum, h is a constant

Question 12

Bohr

Answer 12

just hydrogen atom: central proton, electron in circular orbit
L=mvr and K=1/2mv2
L=nh/2(pi) n is principal quantum number

Question 13

Bohr’s energy of the electron

Answer 13

E=-Rh/n2

Rh is Rydberg unit of energy.

Question 14

Applications of Bohr model

Answer 14

photon is emitted when going down in level.

energy is E=hc/lambda (wavelength of radiation)

Question 15

Lyman series

Answer 15

group of hydrogen emission lines corresponding to transitions rom energy levels greater than 2 to n=1. larger energer transitions than Balmer series, shorter photn wavelengths in UV section

Question 16

Balmer

Answer 16

group of hydrogen emission lines corresponding to transitions rom energy levels greater than 3 to n=2

Question 17

Paschen

Answer 17

group of hydrogen emission lines corresponding to transitions rom energy levels greater than 4 to n=3

Question 18

quantum mechanics

Answer 18

more electrons: not a clearly defined circular pathway at a fixed distance

Question 19

Heisenberg uncertainty principle

Answer 19

impossible to know both the momentum and position of the electron

Question 20

principal quantum number

Answer 20

n. diffrence in energey between 2 shells decreased as distance from nucleus increases (E=[1/ninitial2-1/nfinal2])

Question 21

angular moment/azimuthal quantum number

Answer 21

l. 0 to n-1. so for n=1, l=0. n=2, l=0 and l=1. s,p.d.f

Question 22

max number of electrons within a subshell

Answer 22

4l+2

Question 23

magnetic quantum number

Answer 23

ml. particular orbital
-l to +l, including 0.
s subshell, l=0, limits ml to 0, so there is only 1 orbital in the s subshell

Question 24

p subshell magnetic quantum number

Answer 24

l=1, ml is -1, 0, 1 so 3 orbitals

Question 25

d subshell magnetic quantum number

Answer 25

l=2, ml is -2, -1, 0, 1, 2 so 5 orbitals

Question 26

f subshell magnetic quantum number

Answer 26

l=3 so 7 orbitals

Question 27

electron configuraiton abbreviation

Answer 27

placing the noble gas that precedes the element of interest in brackets

Question 28

Hund’s rule

Answer 28

orbitals are filled so there are a maximum number of half-filled orbitals with parellel spins

Question 29

Exceptions to electron configuration

Answer 29

Chromium and Copper and other elements int heir groups. chromium is [Ar] 4s13d5, copper is AR4s13d10

Question 30

paramagnetic

Answer 30

magnetic field will cause parallel spins in unpaird electrons and cause an attraction

Question 31

diamagnetic

Answer 31

paired electrons will be repelled