4.1 Atomic structure and the Periodic Table

Question 1

What is an atom?

Answer 1

Smallest particle (of an element) capable of exisiting on its own

Question 2

What is the periodic table?

Answer 2

Elements arranged in order of atomic number

Question 3

What is an element?

Answer 3

Substance that cannot be separated into simpler substances by chemical means. Made up of only one type of atom.

Question 4

What is a compound?

Answer 4

Contains atoms of two or more elements chemically combined together

Question 5

What is a mixture?

Answer 5

Two or different chemicals, mixed but not chemically joined together

Question 6

What is filtration?

Answer 6

A method of separating an insoluble solid from a liquid

Question 7

What is fractional distillation?

Answer 7

A method to separate liquids by evaporation and condensation because each liquid has a different boiling point.

Question 8

What is crystallisation?

Answer 8

A method to separate the solute from a solution as the solution evaporates to leave crystals.

Question 9

What is chromatography?

Answer 9

Separates a mixture due to movement of substances through a stationary phase.

Question 10

What is the Plum pudding model of an atom?

Answer 10

A ball of positive charge with negative electrons embedded in it.

Question 11

What is the nuclear model of an atom?

Answer 11

Nucleus containing protons and neutrons orbited by electrons

Question 12

What did Neils Bohr discover?

Answer 12

He adapted the nuclear model by suggesting that electrons orbit the nucleus at specific distances

Question 13

What did James Chadwick discover?

Answer 13

He provided the evidence to show the existence of neutrons within the nucleus.

Question 14

What does the atomic number tell us?

Answer 14

The number of protons in an element

Question 15

What is the radius of an atom?

Answer 15

0.1 nm (1 x 10-10 m)

Question 16

What is the radius of a nucleus?

Answer 16

Less than 1/10 000 of that of the atom (about 1 x 10-14 m).

Question 17

What is the mass number?

Answer 17

Total number of protons and neutrons

Question 18

What are isotopes?

Answer 18

Atoms of the same element, which have the same number of protons and a different number of neutrons

Question 19

How did they order the elements in the early periodic table?

Answer 19

In order of atomic weights

Question 20

What did Mendeleev do with the Periodic Table?

Answer 20

Overcame problem of elements in inappropriate groups by leaving gaps for undiscovered elements and changed some elements groups

Question 21

What do metals form when they react?

Answer 21

Positive ions

Question 22

What do non-metals form when they react?

Answer 22

Negative ions

Question 23

What are noble gases and what are their properties?

Answer 23

Elements in group 0. They are unreactive because they have a full outer shell of electrons

Question 24

What happens to the boiling points of group 0?

Answer 24

Boiling points increase down the group

Question 25

What are the alkali metals?

Answer 25

Group 1

Question 26

Describe and explain the reactivity of group 1 metals

Answer 26

More reactive as you go down the group. Because outer electron is further away from the positive nucleus, so there is less attraction and the electron is lost more easily.

Question 27

How do group 1 metals react with water?

Answer 27

Form a metal hydroxide and hydrogen

Question 28

What are the halogens and how are they found?

Answer 28

Group 7 and found as diatomic elements

Question 29

What happens to the metlting point of group 7?

Answer 29

Melting points increase down the group

Question 30

Describe and explain the reactivity of group 7

Answer 30

Less reactive as you go down the group. Because outer electrons are further away from the positive nucleus, so there is less attraction and the electron is gained less easily.

Question 31

What is a displacement reaction with group 7?

Answer 31

A more reactive halogen displaces a less reactive halogen from an aqueous solution of its salt.