the periodic table

Question 1

who developed the periodic table

Answer 1

dimitri mendeleev

Question 2

give two things mendeleev did

Answer 2

arranged known elements in order of atomic weight, grouped elements with similar properties together, left gaps for elements that had not yet been discovered

Question 3

what is group one on the periodic table

Answer 3

the alkali metals

Question 4

name three alkali metals

Answer 4

lithium, sodium, potassium

Question 5

give properties of alkali metals

Answer 5

low density, very reactive,

Question 6

why are they stored in oil

Answer 6

they react with air

Question 7

does group one reactivity increase up or down the group

Answer 7

down

Question 8

what is group seven on the periodic table

Answer 8

the halogens

Question 9

name three halogens

Answer 9

flourine, chlorine, bromine

Question 10

give two properties of halogens

Answer 10

diatomic (Cl2) (I2) (Ts2), boiling/ melting points go up down the group, poisonous non metals, less reactive down the group

Question 11

what chemical dissolves the halogens and causes them to change colour

Answer 11

cyclohexane

Question 12

what are the elements with no group called

Answer 12

transition elements

Question 13

give three properties of the transition elements

Answer 13

hard and strong, high density, relatively high melting and boiling points, can form more ions - +2,+3, can be used as catalysts