C2

Question 1

Who made one of the First suggestions for a periodic table

Answer 1

John Dalton

Question 2

What was John Dalton’s Idea

Answer 2

Arranged elements in order of their atomic weights

Question 3

Who improved John Daltons Ideas?

Answer 3

John Newland

Question 4

What did John Newland change?

Answer 4

Arranged the elements in order of mass but noticed every 8th element had similar properties. He called this the “law of octaves”

Question 5

What Mistakes did John Newland Make?

Answer 5

-Thought all the elements were discovered
-Pattern of 8 Broke down after calcium because of the undiscovered elements

Question 6

Who Imprpved on John Newlands Ideas?

Answer 6

Mendeleev

Question 7

What did Mendeleev change?

Answer 7

Left gaps for elements that had not been discovered and used the table to predict their properties

Question 8

What were problems with Mendeleevs Table and why?

Answer 8

Argon atoms have greater relative mass than potassium atoms but ordering it that way would put argon in reactive metals so he rearranged them to fit

Question 9

How was Mendeleevs problem solved later?

Answer 9

-Elements now ordered by number of protons
-Isotopes were the cause of unexplainable mass

Question 10

What does periodic mean in the term periodic table?

Answer 10

Patterns occuring in intervals

Question 11

What are Reactive metals

Answer 11

-Found in Group 1 and 2
-Reactive with other elements
-Most react with water
-All soft

Question 12

Transition metals

Answer 12

-Common metals like iron,copper,silver and gold
-Not very reactive-unreactive
-No group between group 2 and 3

Question 13

Non Metals

Answer 13

-Starts at Boron in group 3 and goes diagonally across to group 7 (looks like stairs)
-Low melting and boiling points
-Liquids or gases at room temperature (20c)

Question 14

Noble gases

Answer 14

-Found in group 0
-8 electrons in outer shell not 0
-Very unreactive
-Hard to combine with other elements

Question 15

Do metal atoms lose or gain electrons

Answer 15

Lose

Question 16

Do non-metals lose or gain electrons

Answer 16

Gain

Question 17

Why are noble gases unreactive

Answer 17

Because of their very stable electron arrangements. Full outer shell

Question 18

What are Alkali metals

Answer 18

-Elements found Group 1
-Melting and boiling points decrease going down the group
-All react with water
-All form 1+ ions

Question 19

Does reactivity Increase or Decrease going down Alkali metals

Answer 19

Increases

Question 20

Balanced symbol equation for sodium reacting with water

Answer 20

2Na(s) + 2H₂O(l) > 2NaOH(aq) + H₂(g)

Question 21

Balanced symbol equation for potassium reacting with water

Answer 21

2K(s) + 2H₂O(l) > 2KOH(aq) + H₂(g)

Question 22

What happens when sodium lithium or potassium reacts with water

Answer 22

Metal floats on the water moves and fizzes. Fizzing occurs because metal reacts with water to form hydrogen gas and produces a metal hydroxide. Universal indicator turns purple

Question 23

What happens differently when Potassium reacts with water

Answer 23

Vigorously reacts and hydrogen produced from the reaction ignites with a lilac flame. Also produces a metal hydroxide

Question 24

Word equation for sodium reacting with water

Answer 24

Sodium + water > sodium hydroxide + hydrogen

Question 25

Word equation for potassium reacting with water

Answer 25

Potassium + Water > Potassium Hydroxide + Hydrogen

Question 26

What other elements do alkalis react vigorously with

Answer 26

Non-metals e.g chlorine gas. Produces Metal Chlorides which all dissolve readily in water to form colourless solutions.

Question 27

Why do reactions get more vigorous as you go down the group

Answer 27

Becomes easier to lose the single electron in the outer shell

Question 28

What are Halogens

Answer 28

-Found in Group 7 -Toxic non metals -low melting and boiling points -poor conductors of heat and electricity -element made up of diatomic molecules

Question 29

What are diatomic molecules

Answer 29

Pairs of atoms joined together by a covalent bond

Question 30

Does reactivity increase or decrease going down halogens

Answer 30

Decrease

Question 31

What happens when halogens react with other non metal atoms?

Answer 31

They Form covalent compounds

Question 32

What happens when halogens react with metal atoms

Answer 32

They form ionic compounds. They always gain one electron from the metal to have a full outer shell so will have a 1- charge. Name also gains ide at the end e.g fluorine to fluoride

Question 33

What do periods signify in the periodic table

Answer 33

-The number of shells the atom has -The increasing positive charge (more protons) on the nucleus electrostatic making attraction stronger

Question 34

What happens to atoms with more shells and why

Answer 34

Lose electrons more easily, gain electrons less easily. Because electrons in outer shell are further away from the electrostatic attraction of the nucleus

Question 35

Why do Halogens Decrease in reactivity going down the periods

Answer 35

-More Shells mean harder to gain new electron because further from nuclei's electrostatic attraction -nucleus shielded by more inner shells reducing electrostatic attraction -Although has increased nuclear charge it is oughtweighed by these two factors

Question 36

Why do Alkalis Increase in reactivity going down the periods?

Answer 36

Alkalis lose electrons to gain full outer shell so find it easier to so when there is less electrostatic attraction holding them to the nucleus

Question 37

What elements were not dsicovered when mendeleev's version of the periodic table was published

Answer 37

The Noble Gases