group 1 & group 7 (35-36) (paper 1)

Question 1

what is the name given to group 1 metals

Answer 1

the alkali metals

Question 2

what can simple reactions with metals determine for an element

Answer 2

if it is in the same family it will react a similar way

Question 3

what is the word equation for a group 1 reacting with water

Answer 3

metal + water -> metal hydroxide + hydrogen

Question 4

what is the chemical equation for a group 1 reacting with water (lithium)

Answer 4

2Li(s) + 2H2O(l) -> 2LiOH(aq) + H2(g)

Question 5

what is the word equation for a group 1 reacting with oxygen

Answer 5

metal + oxygen -> metal oxide

Question 6

what is the chemical equation for a group 1 reacting with oxygen (lithium)

Answer 6

4Li(s) + O2(g) -> 2Li2O(s)

Question 7

does lithium form anything other than lithium oxide when reacting with oxygen

Answer 7

no

Question 8

does sodium form anything other than sodium oxide when reacting with oxygen

Answer 8

yes - sodium peroxide

Question 9

what would you observe when lithium reacts with water

Answer 9

• fizzes
• moves on surface of water
• floats
• universal indicator turns blue

Question 10

what would you observe when sodium reacts with water

Answer 10

• melts into a ball
• moves quick on surface of water
• fizzes
• universal indicator turns blue

Question 11

what would you observe when potassium reacts with water

Answer 11

• purple flame
• explodes
• forms a ball
• floats
• universal indicator turns blue

Question 12

what happens to the reactivity as you go down the group 1 elements

Answer 12

they are more reactive further down

Question 13

why are group 1 elements more reactive down the group

Answer 13

• all have 1 electron on the oouter shell
• down the group the outer most electron is further from the nucleus
• less attraction between the nucleus and electron
• electron more easily lost = more reactive

Question 14

what group does the name halogens refer to

Answer 14

group 7

Question 15

describe physically chlorine in room temperature

Answer 15

green gas

Question 16

describe physically bromine in room temperature

Answer 16

red-brown liquid with orange vapour

Question 17

describe physically fluorine at room temperature

Answer 17

pale yellow gas

Question 18

describe physically iodine at room temperature

Answer 18

dark gray solid which sublimes to a purple vapour

Question 19

how would you write the group 7 elements moleculally

Answer 19

X2 ~ eg Cl2

Question 20

what happens to the boiling point as you go down group 7

Answer 20

it increases

Question 21

what happens to the reactivity as you go down the group 7 elements

Answer 21

the reativity decreases ~ fluorine most reactive then chlorine etc

Question 22

why are the group 7 elements most reactive at the top of the group

Answer 22

• they all need 1 more electron
• it is easier for a halogen atom to attract an electron as a smaller atom
• there is stronger attraction forces between the needed electron and the nucleus