atomic structure

Question 1

What are atoms made of?

Answer 1

1) protons
2) neutrons
3) electrons

Question 2

What volume of an atom is occupied by its nucleus?

Answer 2

0.1%

Question 3

What is the mass of an electron?

Answer 3

1/1836 the mass of a proton

Question 4

What is the mass of an atom?

Answer 4

1) 1 atomic mass unit
2) 1/12 mass carbon-12
3) 1.67 x 10⁻²⁷ kg
4) 1 Dalton

Question 5

What is the diameter of an atom?

Answer 5

10⁻¹⁰ m = 0.1 nm

Question 6

What is the diameter of a nucleus?

Answer 6

10⁻¹⁵ m = 0.001 pm

Question 7

isotope

Answer 7

atoms with same atomic number (Z) but different mass number (A)

Question 8

Z

Answer 8

atomic number

Question 9

A

Answer 9

mass number

Question 10

Do all atoms have isotopes?

Answer 10

yes

Question 11

What is the medical source of radioactivity?

Answer 11

cobalt-60

Question 12

How is cobalt-60 made?

Answer 12

by bombarding cobalt-59 with neutrons

Question 13

What are the 7 characteristic properties of atoms?

Answer 13

1) possess Mass
2) contain Electrons
3) Combine with one another
4) Have various properties
5) Attract one another
6) contain positive Nuclei
7) Occupy volume

Question 14

frequency (v) =

Answer 14

number of waves per unit time

Question 15

speed of light (c) =

Answer 15

frequency (v) x wavelength (λ)

Question 16

photon

Answer 16

light that comes in a bundle / packet

Question 17

energy (E) =

Answer 17

Planck’s constant (h) x frequency (v)

Question 18

Planck’s constant

Answer 18

6.626 x 10⁻³⁴ J s

Question 19

energy of an electron, E =

Answer 19

1/2mv²

Question 20

wavelength of an electron, λ =

Answer 20

hv

Question 21

Does an electron have magnetic properties?

Answer 21

yes

Question 22

Heisenberg’s uncertainty principle

Answer 22

1) electrons have wave properties + so are always spread out rather than in one place
2) position of a moving electron cannot be defines
3) electrons are described as delocalised as their waves are spread out rather than pinpointed
4) the more accurately we know the position of an electron, the more uncertain we are about its motion

Question 23

orbital

Answer 23

probable location of an electron

Question 24

What 4 quantum numbers does an electron have?

Answer 24

1) principal quantum number (n)
2) azimuthal quantum number (l)
3) magnetic quantum number (mₗ)
4) spin quantum number (mₛ)

Question 25

principal quantum number (n)

Answer 25

1) describes energy of orbital
2) positive integer
3) as n increases energy of electrons increase + orbital size increases

Question 26

azimuthal quantum number (l)

Answer 26

1) describes angular momentum
2) describes shape of orbital
3) 0 or positive integer

Question 27

magnetic quantum number (mₗ)

Answer 27

1) describes directionality
2) describes number of restricted orientations
3) integer between +l and -l

Question 28

spin quantum number (mₛ)

Answer 28

1) describes spin direction

2) +1/2 or -1/2

Question 29

Pauli exclusion principle

Answer 29

each electron in an atom has a unique set of quantum numbers

Question 30

How many electrons can an orbital have?

Answer 30

2

Question 31

Hund’s rule

Answer 31

the lowest energy configuration involving orbitals of equal energy is the one with the maximum number of electrons in the same spin orientation