periodic tables

Question 1

why elements in same group same properties

Answer 1

same no. electrons in outer shel which they need to loose/gain

Question 2

alkali metals physical properties

Answer 2

low mtp
less dense
soft
(unusual for metals)

Question 3

alkali metals stored in oil

Answer 3

to not react with oxygen in the air

Question 4

alkali metals no. electrons in outer shell

Answer 4

1

Question 5

alkali metals observations reacting with water

Answer 5

Li - effervescence- moves on surface
Na - effervescence- moves on surface - melts into ball
K - effervescence- moves on surface - melts into ball - lilac flame

Question 6

alkali metals react with water

Answer 6

metal + water > metal hydroxide (UI turns blue - alkali) + hydrogen (lit splint - squeaky pop)

Question 7

alkali metals reactivity trend

Answer 7

loose outer shell electron when react
down G1 reactivity increases due to
- more shells - greater distance between nucleus + outer shell electron
- more shells - more shielding
so weaker EA between nucleus + outer shell electron so easier to loose electron

Question 8

alkali metals reaction with oxygen

Answer 8

G1 metals are all white solids

metal + oxygen > metal oxide

Question 9

alkali metals flame test

Answer 9

Li - red
Na - yellow
K - lilac

Question 10

halogens

Answer 10

7 electrons in outer shell
react easily with metals to form ionic compounds form negative ions > HALIDES
exists as diatomic

Question 11

halogen physical properties

Answer 11

go from gas to solid down G7
down G7 colour darker
down G7 mtp and bp increase

Question 12

fluorine colour

Answer 12

pale yellow gas
pale yellow vapour
colourless (aq)

Question 13

chlorine colour

Answer 13

pale green gas
pale green vapour
colourless (aq)

Question 14

bromine colour

Answer 14

red-brown liquid
orange vapour
orange(aq)

Question 15

iodine colour

Answer 15

dark grey solid
purple vapour
brown(aq)

Question 16

halogens trend in mtp and bp

Answer 16

down G7 mtp and bp increase

• relative molecular mass increases
• intermolecular forces get stronger + harder to overcome

Question 17

displacement reaction - chlorine and potassium bromide

Answer 17

chlorine displaces bromine

chlorine is more reactive

Question 18

halogens reactivity trend

Answer 18

as you go down G7 reactivity decreases
- more shells - more distance between nucleus and outer shell
- more shells - more shielding
so weaker EA between nucleus and outer shell electron
harder to gain electron

Question 19

redox reaction

Answer 19

a chemical reaction involving the transfer of one or more electrons from one reactant to another
(oxidation reduction reaction)

Question 20

what happens in redox reaction

Answer 20

Cl2 + 2Br- > 2Cl- + Br2
Cl2 sharing electrons (covalent) and 2Br- has gained electrons (ionic)
Cl2 prefers to gain electrons not share so takes electrons from Br (more reactive)
now Br2 sharing electrons (covalent) and 2Cl- has gained electrons (ionic)

Question 21

OILRIG

Answer 21

oxidation
is 
loss
reduction
is 
gain

Question 22

ionic equation

Answer 22

splint anything ionic and aqueous into ions cancel out spectator ions (same on both sides)