1.6 periodic table

Question 1

n terms of sub-shells, how is the periodic table divided up?

Answer 1

division of electronic shells separated by orbitals which are divided into s, p, d and f blocks. the name of the block shows the orbital in which the elements outer electron lies

Question 2

what are the rules of electronic configuration?

Answer 2

electrons always enter the lowest energy orbital available. prefer to occupy orbitals on their own and will only pair up if there is no empty orbital of the same energy left.

Question 3

flame test 3 compounds:

Answer 3

wire/damp splint dipped in compounds and placed on roaring flame.

potassium bromide = lilac flame
barium chloride = apple-green flame
calcium iodide = brick-red flame

Question 4

flame test observations ( cations )

Answer 4

Li+ = brick red
Na+ = orange/yellow
K+ = lilac
Ca+ = brick red
Sr+ = crimson red
Ba+ = apple green

Question 5

silver nitrate test observations ( anions )

Answer 5

dissolve some of each compound in a small amount of water and add silver nitrate solution

Cl- = white ppt
Br- = cream ppt
I- = yellow ppt

Question 6

silver nitrate test observations ( anions )

Answer 6

a level extra = solution in NH3
Cl- = ppt dissolves in dilute NH3
Br- = ppt dissolves slightly in concentrated NH3
I- = no change insoluble in NH3

Question 7

why do the halogens exist in different states at room temp?

Answer 7

at room temp chlorine is gaseous, bromine is a liquid and iodine is a solid due to their different boiling points

Question 8

explain the trend in volatility

Answer 8

the most reactive would be fluorine. halogens react by gaining electrons to form negative halide ions. as you go down the group the outer electrons are shielded more and are further away from the positive pull of the nucleus.

Question 9

displacement reactions observations:

Answer 9

( sodium ) iodide turns brown with both chlorine and bromine substances
( sodium ) bromide turns orange with chlorine
no reaction happens when iodine is added to anything

Question 10

displacement reactions conclusions:

Answer 10

chlorine displaces both bromine and iodine with bromide/Iodide solution therefore chlorine is most reactive
bromine displaces iodine from iodide solution meaning more reactive than iodine.
more reactive halogens displace less reactive halogens from solution trend in reactivity.

Question 11

gravimetric analysis method:

Answer 11

unknown chloride poured into beaker
add more drops of silver nitrate - forms ppt until no further ppt forms
filter, wash and dry ppt
heat to get a constant mass
subtract mass of filter paper from mass of ppt and with filter paper at the end.

Question 12

what is the trend in thermal stability for group 2 carbonates?

Answer 12

thermal stability increases as you go down the group. all group 2 carbonates decompose on heating to the oxide and carbon dioxide.

Question 13

group 1 and 2 carbonates

Answer 13

both group carbonates show different properties. G1 are soluble and G2 are insoluable