Topic 1 - Atomic Structure And The Periodic Table

Question 1

What does the atomic number tell you?

Answer 1

How many protons there are

Question 2

What does the mass number tell you?

Answer 2

The total number of protons and neutrons in the atom

Question 3

Definition of element

Answer 3

An element is a substance that consists of only one type of atom

Question 4

Definition of ‘Isotope’

Answer 4

Different forms of the same element, which have the SAME number of PROTONS but a DIFFERENT number of NEUTRONS

Question 5

Extra info on isotopes…

Answer 5

• Isotopes are the same as the element except for extra NEUTRONS
• Isotopes have the same atomic number but different mass numbers

Question 6

Popular example of a pair of isotopes?

Answer 6

Carbon-12 and Carbon-13

Carbon-12
6 PROTONS
6 ELECTRONS
6 NEUTRONS

Carbon-13
6 PROTONS
6 ELECTRONS
7 NEUTRONS

Question 7

What do we refer to when talking about the mass of element as a whole?

Answer 7

• Relative atomic mass (Ar) is used instead of mass number when referring to the element as a whole.
• Why? Because many elements exist as a number of different isotopes, takes it into account

Question 8

Relative Atomic Mass definition

Answer 8

Relative atomic mass is an average mass taking into account the different masses and abundance’s (amounts) of all the isotopes that make up the element

Question 9

Formula for RAM

Answer 9

RAM (Ar) = sum of (isotope abundance x isotope mass number)
———————————
Sum of abundances of all the isotopes

Question 10

Compounds (brief)

Answer 10

• Atoms join together to make compounds
• When elements react, atoms combine with other atoms to form compounds
• Properties of a compound are usually totally different from properties of the original elements.

Question 11

Compounds (in-depth)

Answer 11

• Compounds are substances formed from two or more elements
• The atoms of each are in fixed proportions throughout the compound
• atoms held together by chemical bonds

Question 12

What making bonds involves:

Answer 12

• Making bonds involves atoms giving away, taking or sharing electrons
• Only electrons involved, nuclei of atoms aren’t affected at all when a bond is made

Question 13

Can you separate original elements of a compound?

Answer 13

It’s usually difficult to separate original elements of a compound out again, chemical reaction needed to do so

Question 14

Ionic bonding

Answer 14

• A compound formed from a metal and a non-metal consists of ions
• Metal atoms = lose electrons to form positive ions
• Non-metal atoms = gain electrons to form negative ions
• Opposite charge of ions mean that they’re strongly attracted to each other (called ionic bonding)

Question 15

Examples of compounds which are bonded ionically:

Answer 15

• Sodium chloride
• Magnesium oxide
• Calcium oxide

Question 16

NaCl Sodium Chloride, how is it bonded ionically

Answer 16

A sodium atom gives an electron to a chlorine atom.

Question 17

Covalent bonding

Answer 17

• A compound formed from a non-metal consists of molecules

- Each atom shares an electron w/ another atom (called covalent bonding)

Question 18

Hcl Hydrogen Chloride, how is it bonded covalently?

Answer 18

A hydrogen atom bonds w/ a chlorine atom by sharing an electron w/ it

Question 19

Iron reacts with sulphur?

Answer 19

The compound formed is a dull grey solid lump, doesn’t behave anything like iron or sulphur.

Question 20

Formula

Answer 20

• Represents a compound
• Made up of elemental symbols
• Shows what atoms are in a compound

Question 21

Carbon Dioxide (CO2)

Answer 21

• A compound formed from a chemical reaction between carbon and oxygen
• Contains 1 carbon atom and 2 oxygen atoms

Question 22

Sulphuric acid (H2SO4)

Answer 22

Each molecule contains: 2 hydrogen atoms, 1 sulphur atom and 4 oxygen atoms

Question 23

Calcium Hydroxide Ca(OH)2

Answer 23

Contains 1 calcium atom, 2 oxygen atoms and 2 hydrogen atoms

Question 24

What does a bracket in a formula mean (e.g. Ca(OH)2)?

Answer 24

Means that the little number outside applies to everything inside the brackets

Question 25

Carbon dioxide

Answer 25

CO2

Question 26

Ammonia

Answer 26

NH3

Question 27

Water

Answer 27

H2O

Question 28

Sodium chloride

Answer 28

NaCl

Question 29

Carbon monoxide

Answer 29

CO

Question 30

Hydrochloric acid

Answer 30

HCl

Question 31

Calcium Chloride

Answer 31

CaCl2

Question 32

Sodium carbonate

Answer 32

Na2CO3

Question 33

Sulphuric acid

Answer 33

H2SO4

Question 34

Word Equation

Answer 34

How to show a chemical reaction

Question 35

Symbol equations

Answer 35

- Shows the atoms on both sides - Shows chemical changes - Uses symbols or formulas

Question 36

Mixture

Answer 36

- Easily separated - No chemical bond between diff. parts of mixture - parts of mixture can be either elements or compounds - can be separated out by physical methods

Question 37

Physical method

Answer 37

One that doesn’t involve a chemical reaction, so doesn’t form any new substances.

Question 38

Examples of physical methods (mixtures)

Answer 38

- Filtration - Crystallisation - Simple distillation - Fractional distillation - Chromatography

Question 39

Air (mixture)

Answer 39

- A mixture of gasses (mainly nitrogen, oxygen, carbon dioxide and argon) - gasses can be separated out fairly easily

Question 40

Crude oil

Answer 40

A mixture of different length hydrocarbon molecules

Question 41

Properties of a mixture

Answer 41

- The properties of a mixture are just a mixture of the properties of the separate parts. - Chemical properties of substance not affected by it being part of a mixture

Question 42

A mixture of iron powder and sulphur powder

Answer 42

- Will show properties of both iron and sulphur | - Will contain grey magnetic bits of iron, bright yellow bits of sulphur