C2

Question 1

what did john dalton do

Answer 1

he arranged the elements in their atomic weights

Question 2

what did mendeleev do

Answer 2

he arranged the elements discovered by atomic mass and left gaps for undiscovered elements by looking at properties of elements next to that gap and by doing so he could predict the properties of elements which had not been discovered yet.

Question 3

what are some properties of the alkali metals

Answer 3

soft
low densities
low melting points

Question 4

which group are the alkali metals

Answer 4

group 1

Question 5

the reactivity of the group 1 elements and why it happens that way

Answer 5

reactivity increases as you go down the group due to the atom’s radius increasing and so the electrons get further away from the nucleus; reducing the attractive force between the nucleus and the electrons and so making it easier to lose an electron.

Question 6

why does the melting and boiling point decrease as you go down group 1

Answer 6

as it gets easier to lose an electron as you go down the group.

Question 7

name the formula for the reaction between an alkali metal and water

Answer 7

alkali metal + water —> metal hydroxide + hydrogen

Question 8

what would you see if lithium reacted with water

Answer 8

will float and move around slowly and a gas would be formed

Question 9

what would you see if sodium reacted with water

Answer 9

it would float and move around quickly and would release a gas

Question 10

what would you see if potassium reacted with water

Answer 10

would move the fastest, have a lilac flame and would release a gas

Question 11

what are the halogens

Answer 11

they are non-metals

Question 12

which group are the halogens in

Answer 12

group 7

Question 13

are alkali metals diatomic

Answer 13

no

Question 14

are halogens diatomic

Answer 14

yes

Question 15

are noble gases diatomic

Answer 15

no

Question 16

why does the reactivity of the halogens decrease going down the group

Answer 16

the molecules get bigger making it HARDER TO GAIN an electron due to the outer shells being further away from the nucleus

Question 17

what’s the state of matter of fluorine at room temp

Answer 17

gas

Question 17

why does the boiling/melting point decrease going down the group 7

Answer 17

the molecules get bigger making it HARDER TO GAIN an electron due to the outer shells being further away from the nucleus

Question 18

what’s the state of matter of chlorine at room temp

Answer 18

gas

Question 19

what’s the state of matter of bromine at room temp

Answer 19

liquid

Question 20

what’s the state of matter of iodine at room temp

Answer 20

solid

Question 21

why is the reaction of fluorine with hydrogen dangerous?

Answer 21

very explosive

Question 22

why is the reaction of chlorine with hydrogen dangerous?

Answer 22

quite explosive

Question 23

what is needed for a reaction of Bromine with hydrogen

Answer 23

reacts at 300 degrees Celsius with a catalyst

Question 24

what are the requirements of a reaction of Iodine with hydrogen

Answer 24

reacts at 300 degrees Celsius with a catalyst very slowly

Question 25

state the reaction of an alkali metal with a halogen

Answer 25

alkali metal + halogen —> metal halide

e.g sodium + bromine —> sodium bromide

Question 26

what are the properties transition metals

Answer 26

shiny
good conductors of heat and electricity
hard
strong
high density
are malleable
are ductile

Question 27

transition metal reactivity

Answer 27

are much less reactive than the alkali metals and they tend to react slowly.

Question 28

u are

Answer 28

done