CHAPTER 2 chemistry

Question 1

Properties of alkali metals

Answer 1

Very reactive
Low density
Soft 
Relatively low melting and boiling points 
Form 1+ ions

Question 2

Properties of halogens

Answer 2

Low melting and boiling points
Poor conductors of heat and electricity
Reactivity decreases down the group

Question 3

Characteristics of transition elements

Answer 3

Good conductors of heat and electricity
Hard and strong
Dense
High melting and boiling points

Question 4

Which scientists ordered elements in terms of their weight

Answer 4

Dalton

Question 5

What did Mendeleev do

Answer 5

created the periodic table based on atomic weight and left gaps for undiscovered elements

Question 6

what are elements in order of in the periodic table

Answer 6

proton number

Question 7

what does the group of an atom tell us

Answer 7

the number of electrons in outer shell

Question 8

main difference between metals and non metals

Answer 8

metals conduct electricity where most non metals are insulators

Question 9

where are non metals found

Answer 9

rhs

Question 10

what is different about noble gases

Answer 10

have full outer shell

Question 11

how do metals react

Answer 11

losing outer electrons

Question 12

how do non metals react

Answer 12

gaining electrons

Question 13

what determines an element chemical properties

Answer 13

number of electrons in outer shell

Question 14

what happens in a halogen displacement

Answer 14

a more reactive halogen displaces a less reactive halogen

Question 15

why does reactivity increase going down group 1

Answer 15

they need to lose one electron which is easier the further away it is from the centre

Question 16

why does reactivity decrease going down group 7

Answer 16

they need to gain one electron but the forces of attraction are weaker in the outer shells

Question 17

properties of transition elements

Answer 17

good conductors
hard
dense
high melting points

Question 18

what are transition elements often used as

Answer 18

catalysts

Question 19

what did Dalton do to create the periodic table

Answer 19

arranged elements in order of atomic weights

Question 20

what did newlands do to create the periodic table

Answer 20

proposed the law of octaves where the proposer ties of every eighth element were similar

Question 21

what was mendeleevs breakthrough

Answer 21

he left gaps I the periodic table for yet to be discovered elements

Question 22

how are elements organised in the periodic table now

Answer 22

by increasing proton atomic number

Question 23

what does the group an element is in tell you

Answer 23

how many electrons are in the outer shell

Question 24

why are noble gases very unreactive

Answer 24

full outer shell

Question 25

reaction of alkali metals with water

Answer 25

float on water
fizzes
move around

Question 26

what is produced when an alkali metal reacts with water

Answer 26

metal hydroxide and hydrogen gas

Question 27

why are alkali metals stores under oil

Answer 27

react with oxygen in air

Question 28

what do the halogens all exist as

Answer 28

molecules

Question 29

what colour in fluorine

Answer 29

yellow

Question 30

what colour is chlorine

Answer 30

green

Question 31

what colour is bromine

Answer 31

red-brown

Question 32

what colour is iodine

Answer 32

purple

Question 33

as you go down group 7 …

Answer 33

less reactive

higher melting and boiling point

Question 34

what are the two types of bonds halogens can make

Answer 34

ionic bonds with metals

covalent bonds with non metals

Question 35

what ions do halogens form

Answer 35

1-

Question 36

why do halogens get less reactive down the group

Answer 36

further from the nucleus so harder to extra an extra electron

Question 37

what happens in a halogen displacement reaction

Answer 37

a more reactive one will displace a less reactive one from its salt

Question 38

why does reactivity increase down group 1

Answer 38

the atoms get larger so the single electron they want to lose is farther away from the nucleus

Question 39

what is the force called between nucleus and electrons

Answer 39

forces of attraction

Question 40

what sub atomic particles can change forces of attraction

Answer 40

electrons can shield outer electrons from nucleus

Question 41

physical properties of transition elements

Answer 41

good conductors
hard and strong
high melting point

Question 42

what is special about ions of transition metals

Answer 42

can form 2+ or 3+ ions

Question 43

how to tell whether 2+ or 3+ ion

Answer 43

look at roman numerals