Atomic Structure

Question 1

what is the atom

Answer 1

the basic building block of matter. representing the smallest unit of a chemical element

Question 2

what is an atom composed of

Answer 2

subatomic particles namely, protons, neutrons and electrons

Question 3

what forms the nucleus?

Answer 3

protons and neutrons form the core of the atom

Question 4

orbitals

Answer 4

characteristic regions of space that lie outside the nucleus.

Question 5

what lies in the orbital

Answer 5

electrons

Question 6

element

Answer 6

composed of atoms that show similar chemical properties and cannot be further broken down by chemical means

Question 7

protons

Answer 7

carry a single positive charge and have an atomic mass unit (amu) of one. resides in the nucleus of an atom

Question 8

the atomic number

Answer 8

(z) of an element is equal to the number of protons found in an atom of an element. all atoms of a single element have the same atomic number

Question 9

neutrons

Answer 9

reside within the nucleus of an atom and has no charge. has the amu of slightly larger than one.

Question 10

isotopes

Answer 10

different isotopes meaning the same element has a different number of neutrons but the same number of protons

Question 11

mass number

Answer 11

the number of neutrons and protons added together

Question 12

electrons

Answer 12

has a negative charge equal to that of protons just opposite and smaller amu (doesn’t effect mass) and lie in the orbitals outside the nucleus

Question 13

valence electrons

Answer 13

the electrons furthest away from the nucleus and have a weaker magnetic pull towards the nucleus. more likely they are to be influenced by other atoms

Question 14

ion

Answer 14

an atom that has a positive or negative charge due to the loss or gain of electrons

Question 15

atomic weight

Answer 15

is the weight in grams of one mole (mol) of a given element and is expressed in g/mol

Question 16

mole

Answer 16

is a unit used to count particles and is represented Avagadros’ number

Question 17

Avagadros number

Answer 17

6.022*10^23

Question 18

Isotopes convention

Answer 18

described by the name of the element followed by the mass number.
for example carbon-12 or carbon-14

Question 19

ground state

Answer 19

the electron is at its lowest energy state. the smaller the radius the lower the energy state of the electron

Question 20

excited states process

Answer 20

when an electron is excited to a higher energy state, either by heat or other energy. it does not remain here. when it reverts back to ground state it emits energy in the form of photons

Question 21

atomic emission spectrum

Answer 21

because each element can have its electrons excited to different distinct energy levels they each possess this finger print of emission expressed in light

Question 22

Balmer series

Answer 22

emission lines between upper levels n>2 to n=2 (four wave lengths in the visible region)

Question 23

Lyman series

Answer 23

emission line corresponding to transitions between upper levels n>1 to n=1 (higher energy transitions, occur in the UV region)

Question 24

absorption spectrum

Answer 24

the excitation of electrons in a particular element results in energy absorption at specific wavelengths. they correspond directly to emission since the energy difference between levels remains unchanged.

Question 25

Pauli exclusion principle

Answer 25

no two electrons in a given atom can have the same set of 4 quantum numbers.

Question 26

quantum numbers

Answer 26

the “address of an electron” set of four described by n, l ml, ms

Question 27

principal quantum number

Answer 27

denoted by n, which describes the size of the orbital. the larger the the integer of value in the greater energy level and radius of the electrons orbit.

Question 28

energy difference between shells

Answer 28

the difference in energy between adjacent shells decreases as the distance for the nucleus increases.

Question 29

azimuthal quantum number

Answer 29

second quantum number and is denoted by l, refers to the sub shell that occur within each principal energy level. range of 0 to n-1.
s=0 p=1 d=2 f=3

Question 30

sub shells

Answer 30

s,p,d,f

Question 31

magnetic quantum number

Answer 31

the third quantum number and is designated ml.
specifies the particular orbital within a sub shell where an electron is highly likely to be at a point in time. can range from l to -l, including 0

Question 32

how many orbitals and electrons does s have

Answer 32

1 orbital 2 electrons max

Question 33

how many orbitals and electrons does p have

Answer 33

3 orbitals and 6 electrons max

Question 34

how many orbitals and electrons does d have

Answer 34

5 orbitals and 10 electrons max

Question 35

how many orbitals and electrons does f have

Answer 35

7 orbitals and 14 electrons max

Question 36

spin quantum number

Answer 36

fourth quantum number call the spin is denoted by ms. the spin of a particle are either +1/2 or -1/2.
when ever two electrons are in the same orbital they must have opposite spins

Question 37

paired electrons

Answer 37

electrons with opposite spins in the same orbital are often referred to as paired.

Question 38

electron configuration

Answer 38

for a given atom or ion, the pattern by which sub shells are filled and number of electrons within each principal level and sub shell
first number denotes principal level, the letter designates subshell, and the superscript determines the number of electrons in that subshell.

Question 39

(n+l) rule

Answer 39

is used to denote how much energy is in a certain sub shell. the lower the value of the first and second quantum numbers, the lower the energy state. the lower n has the lower energy

Question 40

Hund’s Rule

Answer 40

electrons prefer empty orbitals to half filled ones because pairing energy must be overcome for two electrons carrying repulsive neg charges

Question 41

paramagnetic

Answer 41

if the material has unpaired electrons the magnetic field will align the spins of these electrons and weakly attract the atom

Question 42

diamagnetic

Answer 42

materials that have no unpaired electrons and are slightly repelled by a magnetic feild