module 2: 5.1 electron structure

Question 1

number of electrons in shell number:
1
2
3
4

Answer 1

(2n^2) where n is shell number
2
8
18
32

Question 2

define atomic orbital

Answer 2

an atomic orbital is a region around the nucleus that can hold up to 2 electrons with opposite spins

Question 3

what is the shape of an s-orbital

how many orbitals does it have

Answer 3

the shape of a sphere. it can hold 1 or 2 electrons

n = 1 and has one s-orbital

Question 4

what is the shape of a p-orbital

how many orbitals does it have

Answer 4

the shape of a dumb-bell.

there are 3 separate p-orbitals at 90 degrees to one another

Question 5

how many orbitals does the d-orbital have

Answer 5

n = 3 contains 5 d-orbitals

Question 6

how many orbitals does the f-orbital have

Answer 6

n = 4 contains 7 f-orbitals

Question 7

how do electrons pair (electron-in-box model)

Answer 7

• they pair with opposite spins
• electrons and negatively charge and repel one another
• electrons have a property called spin - either up or down
• an electron is shown as an arrow indicating its spin

Question 8

what are shorthand electron configurations

Answer 8

electron configurations can be expressed more simply in terms of the previous noble gas in the periodic table plus the outer electron sub-shell.

Question 9

define cations

Answer 9

positive ions that are formed when atoms lose electrons

Question 10

define anions

Answer 10

negative ions that are formed when atoms gain electrons