atomic strcuture

Question 1

The shell of an atom is how many times larger than the nucleus?
100
1000
10,000
100,000
1 million

Answer 1

100,000 time larger

Question 2

how many electrons can an f sub-shell hold?
2
3
5
7
8
14
16

Answer 2

14!!

it has 7 orbitals so can hold 2 electrons in each orbital

Question 3

How does electronegativity change as you go across the periodic table?

Answer 3

Electronegativity increases going from left to right and decreases as you go down group. WHY? Electronegativity is the ability of an atom to attract a bonding pair of electrons/HOGGING
left - only 1 valence shell so will give away electron to be stable whilst
right - almost full outer shell so will HOG electrons
whereas if you go down the periodic table its LESS electronegative as electrons can easily be taken

Question 4

What formula describes the maximum number of electrons that can be in a main shell?

Answer 4

2N squared. So 2,8,18, 32 are the max numbers if N=1,2,3,4

Question 5

What is a Valence shell?

Answer 5

the outermost electron shell

Question 6

what does the principle quantum number represent?

Answer 6

• electrons differ in at least 1 number:
principle quantum number n (size of orbital).
Angular quantum number I (shape of orbital),
magnetic quantum number m SIZE OF THE ORBITAL.

other quantum numbers incluDe (orientation of orbital), spin quantum number s (spin of electron with orbital)

Question 7

across a period, why does the radius decrease?

Answer 7

there are more protons in the nucleus so the electrons get DRAWN IN - attracted!
> this also means ionisation energy increases as its harder to remove electrons from attraction

Question 8

what happends to ionisation energy as you go down a group?

Answer 8

the ionisation energy decreases as there is less attraction to the nuclues and MORE SHIELDING of electons

Question 9

what is the unit of absosrbed radiation?
bequeral
svedvurg
siervert
geiger
gray

Answer 9

OPTION E
a- radioactivity
b- sedimentation
c- biololgical damge
d- measuring instrument

Question 10

very weak and easy to break descirbes
intermolecular forces
intramolecular forces

Answer 10

inTERmolecular - between molecules

> inTRA is within molecules and stronge!!`

Question 11

what is the alpha decay of 212/84 Po?

Answer 11

alpha decay is loss of helium nuclei

so its now 208/82 Pb

Question 12

what is beta decay of 24/11 Na?

Answer 12

beta decay is loss of electron

so now its 24/12 Mg

Question 13

What is the maximum number of electrons that can occupy any given orbital, and how do such electrons differ from each other?

Answer 13

2 electrons can occupy one orbital. They spin in opposite directions !!