Atomic Structure and The Periodic Table

Question 1

Who discovered neutrons

Answer 1

Chadwick

Question 2

Who discovered electrons

Answer 2

Thompson

Question 3

Who discovered protons

Answer 3

A series of experiments

Question 4

Who discovered electron shells

Answer 4

Bohr

Question 5

Who discovered the nucleus

Answer 5

Rutherford

Question 6

What did Rutherford discover

Answer 6

nucleus

Question 7

Who conducted the gold foil experiment

Answer 7

Rutherford

Question 8

What order was each part of the atom discovered in

Answer 8

1) electrons (Thompson plum pudding model)
2) nucleus (Rutherford nuclear model)
3) electron shells (Bohr)
4) proton (series of experiments)
5) neutron (Chadwick)

Question 9

What model did Rutherford create of the atom

Answer 9

Nuclear model (atom mostly empty space with electrons orbiting the positive nucleus)

(Electrons had already been discovered so they had to go somewhere in his model but not embedded as he found the atom was mostly empty space so he decided they would orbit around the edge- Bohr then finds that they orbit at set distances)

Question 10

What model did Thompson create of the atom

Answer 10

Plum pudding
Positively charged atom with negative electrons embedded in it

Question 11

True or false, in the nuclear model the electrons orbit the nucleus

Answer 11

True, but not at set distances as Bohr later discovers

Question 12

What was concluded from the gold foil experiment and why

Answer 12

Atom is mostly empty space (most alpha particles went straight through)
Concentrated mass in centre of atom (some alpha particles deflected)
Concentrated mass is positive (some alpha particles reflected)

Question 13

What is the radius of an atom in metres

Answer 13

1x10 ^-10m

Question 14

What is the radius of a nucleus in metres

Answer 14

1x10^-14m

Question 15

4 ways to separate mixtures

Answer 15

Chromotatography
Distillation (fractional and simple)
Crystallisation
Filtration

Question 16

Properties of group 0 elements (Noble gases)

Answer 16

Unreactive due to full outer shell of electrons so they are stable (don’t need to lose or gain any electrons)
Exist as single atoms (are unreactive so don’t bond to form molecules)
Low melting/ boiling point
Boiling points increase down group

Question 17

How does the boiling point change going down group 0 (Noble gases)

Answer 17

Increases

Question 18

What is the name for group 1 metals

Answer 18

Alkali metals (react with water to form an alkali)

Question 19

Why are group 1 elements very reactive

Answer 19

Have 1 electron in outer shell so it is easy to lose just this 1 outer electron and react

Question 20

Does reactivity increase or decrease going down group 1 and why

Answer 20

Increase
- atom increases in size (larger radius)
- outer electron further away from nucleus
- more shells shielding outer electron from nucleus
- weaker electrostatic forces acting between negative outer electron and positive nucleus

Question 21

What happens to boiling point going down group 1

Answer 21

Decreases

Question 22

What happens to boiling point going down group 7 (halogens)

Answer 22

Increases

Question 23

What happens to reactivity going down group 7

Answer 23

Decreases

Question 24

Why does reactivity decrease going down group 7 (but increases going down group 1)

Answer 24

More electron shells so more shielding between nucleus and outer electrons
Weaker electrostatic forces acting between nucleus and outer electrons so harder for an electron to be attracted to the nucleus and to be gained on the outer shell

(In group 7 the atom is trying to gain an electron so further away the electrostatic forces are weaker so there is less attraction meaning it is harder to gain the electron. But in group 1 if further away the electrostatic forces are weaker this means that the outer electron is less attracted to the nucleus so can be more easily lost)

Question 25

Difference between how reactivity changes going down group 1 and group 7

Answer 25

Group 1- increases Group 7- decreases

Question 26

What do group 1 elements form when they react with water

Answer 26

Metal hydroxide + hydrogen

Question 27

What do all halogens exist as

Answer 27

Diatomic molecules (Pairs of atoms chemically bonded together)

Question 28

When 3 or more elements combine with 1 being oxygen what does it end in

Answer 28

Ate

Question 29

Physical properties of alkali metals

Answer 29

Soft Relatively low melting points Low densities

Question 30

Chemical properties of alkali metals

Answer 30

Highly reactive Reactive with water to form metal hydroxides (alkalis)

Question 31

True or false, group 7 elements get darker as you go down the group

Answer 31

True

Question 32

How did John Newlands initially arrange known elements

Answer 32

Order of increasing atomic weight 'Law of Octaves' as elements with similar properties repeated every 8 elements Problem: some elements were grouped together with completely different properties

Question 33

How is the modern periodic table arranged

Answer 33

Increasing atomic number Columns (groups)- all elements in same group have similar chemical properties (react in a similar way due to all having the same number of electrons in their outer shell)

Question 34

How did Mendeleev develop the first modern periodic table

Answer 34

Increasing atomic weight Left gaps for elements yet to be discovered which he predicted the properties of He swapped some elements around

Question 35

Physical Properties of transition metals

Answer 35

High density High melting point Hard Strong Good conductors of heat and electricity Shiny

Question 36

Are alkali metals (group 1) hard or soft

Answer 36

Soft

Question 37

How many times smaller is the nucleus of the atom than the radius

Answer 37

10,000

Question 38

4 differences between physical properties of elements in group 1 and transition metals

Answer 38

Group 1 have lower melting and boiling points, lower densities, are less strong and are softer

Question 39

Further away from the nucleus is there more or less shielding

Answer 39

More (means electrostatic forces between outer electron and nucleus are weaker)

Question 40

Is boiling point chemical or physical property

Answer 40

Physical

Question 41

Fractional vs simple distillation

Answer 41

Fractional distillation separates multiple liquids from a solution based on boiling point (substances with similar boiling point) Simple distillation separates a single liquid from a solution (substances with completely different boiling points) (the solution is heated, evaporated and condensed)

Question 42

What is a compound

Answer 42

2 or more different elements chemically bonded together

Question 43

Does a compound have to be 2 or more different elements

Answer 43

Yes

Question 44

What is a molecule

Answer 44

2 or more atoms chemically bonded together (can be the same type)

Question 45

What is a mixture

Answer 45

Contains 2 or more different substances not chemically joined

Question 46

Why Mendeleev reverse the order of some pairs of elements

Answer 46

So their properties matched the rest of the group

Question 47

4 differences between nuclear model and plum pudding model

Answer 47

Nuclear model has nucleus, plum pudding model does not Nuclear model mostly empty space, plum pudding model is solid Nuclear model positive charge is all in nucleus, plum pudding model atom has overall positive charge Nuclear model electrons orbit nucleus, plum pudding model electrons are embedded into atom

Question 48

Physical property of noble gases (group 0)

Answer 48

Low melting point

Question 49

Why does boiling point increase going down group 0 (noble gases)

Answer 49

Atoms become larger Intermolecular forces between atoms become stronger More energy needed to overcome these forces

Question 50

Chemical properties of group 0 (noble gases)

Answer 50

Un reactive) Full outer shell of electrons)