Atomic Structure

Question 1

How many Elements are there estimated to be in the Periodic Table

Answer 1

Around 100

Question 2

Define an element?

Answer 2

A substance that is made up of only one type of atom e.g. magnesium (Mg) helium (He) oxygen (O2)

Question 3

Define a Compound

Answer 3

Compounds contain two or more different elements chemically combined in a fixed proportion

Question 4

True or False: Compounds usually have identical properties to the elements that they are made from

Answer 4

False; they are usually totally different

Question 5

How can the elements in a compound be separated?

Answer 5

By using a chemical reaction.

Question 6

True or False: In a specific compound, the number of atoms of each element is fixed

Answer 6

True

Question 7

How many atoms of oxygen are there In Al(OH)3

Answer 7

3 Atoms

Question 8

What are the 4 techniques of physical separation

Answer 8

Filtration, Crystallisation, Distillation and Chromatography

Question 9

What are Physical Separation Techniques used for?

Answer 9

Separating Mixtures

Question 10

How do you Separate Elements in a compound

Answer 10

Using a Chemical Reaction

Question 11

What technique is used to separate a insoluble solid from a liquid?

Answer 11

Filtration

Question 12

True or False: Filtration is used to separate a soluble solid from a liquid?

Answer 12

False; Crystallisation is used

Question 13

What happens when a solute (e.g. salt) dissolves in a solvent (e.g.water)?

Answer 13

The bonds holding the solute together break and mix with the particles in the solvent forming a solution.

Question 14

Define a solution?

Answer 14

A mixture of a solute and a solvent which doesn’t separate out.

Question 15

What does the term saturated mean?

Answer 15

No additional solvent will dissolve at that temperature.

Question 16

Define an Isotope?

Answer 16

Isotopes are atoms of an element with different numbers of neutrons.

Question 17

True or false: Atoms have an overall amount of charge

Answer 17

False; atoms do not have any charge. The number of electrons (negatively charged) equals the number of protons (positively charged).

Question 18

Which parts of an atom are charged

Answer 18

Protons and Electrons

Question 19

Define Ions

Answer 19

Ions are atoms that have an overall charge. They have gained or lost electrons.

Question 20

How do you calculate the relative atomic mass of an elements isotopes?

Answer 20

Relative atomic mass = The average of the mass numbers for the different isotopes weighted for the abundance of each isotope.

(M1 x abundance ) + (M2 x abundance) / 100

Question 21

What is the maximum number of electrons that can be held in each of the 4 energy levels (electron shells)

Answer 21

First level - 2
Second level -8
Third level - 8
Fourth level -18

Question 22

Group 1 metals have how many electrons in their outer energy level?

Answer 22

Answer: One - The number of electrons in the outer shell tells us the group number of the element in the periodic table.

Question 23

Elements with full outer shells of electrons are found in which group of the periodic table?

Answer 23

Group 0 - Noble gases

Question 24

What do all of the elements in a group of the periodic table have in common?

Answer 24

1. They have the same number of electrons in their outer shell
2. They react in the same ways

Question 25

How are elements arranged in the modern periodic table?

Answer 25

By atomic number, that is the number of protons.

Question 26

What did Döbereiner call similar elements that appeared in three

Answer 26

Triads

Question 27

What does Newlands’ Law of Octaves state?

Answer 27

That If you arrange the elements in atomic weight, every eighth element reacts in a similar way.

Question 28

Who developed the first modern Periodic Table?

Answer 28

Dmitri Mendeleev

Question 29

Name 2 differences in the modern periodic table compared to Mendeleev’s original Table.

Answer 29

• The elements were arranged in order of atomic mass, whereas now it is ordered by atomic number
• Group 0 (The Noble Gases) was discovered

Question 30

Why are all of the noble gases unreactive?

Answer 30

They have a full outer shell, stabilising the atom.

Question 31

What happens to the boiling points of the noble gases as they go down the group?

Answer 31

The boiling points increase.

Question 32

What happens to the electron structure when metals react?

Answer 32

It loses electrons to achieve a full outer shell.

Question 33

What do all group 1 metals have in common?

Answer 33

They all have 1 electron in their outer shell (and they’re soft).

Question 34

Group 1 metals become more/ less reactive as you go down the group?

Answer 34

More reactive

Question 35

What happens to the outer electron as the elements move down group 1?

Answer 35

It is less attracted to the nucleus and easier to lose. The outer electron is shielded from the nucleus by the internal energy levels.

Question 36

Define a mixture?

Answer 36

A mixture contains 2 or more different substances where the substances are not chemically combined.