Gcse Chemistry Paper 1 Bonding, Structure And Properties Of Matter

Question 1

Define the word compound

Answer 1

2 or (more) different elements that are chemically bonded together

Question 2

What type of atoms form ionic compounds?

Answer 2

A metal
&
Non-metal

Question 3

What type of atoms form covalent compound’s?

Answer 3

2 (or more) non-metals

Question 4

What type of atoms form metallic structures?

Answer 4

Metals

Question 5

In terms of electrons what happens in ionic bonding?

Answer 5

• metals lose electrons

- non-metals gain electrons

Question 6

In terms of electrons what happens in covalent bonding?

Answer 6

Non-metal elements share electrons in pairs

Question 7

In terms of electrons what happens in metallic bonding?

Answer 7

• metal atoms lose an electrons which becomes delocalised and can move through the whole structure.

Question 8

What information does the group number tell you about an element?

Answer 8

The number of electrons in the outer shell

Question 9

How many electrons are in the outer shell of a sodium atom?

Answer 9

1

One

Question 10

What’s the charge of a sodium ion?

Answer 10

+1

Question 11

Why does a sodium atom form ions with a charge of +1?

Answer 11

• has 1+ electron in its outer shell
• loses the electron
• to get an empty outer shell ( noble gas configuration

Question 12

How many electrons are there in a chlorine atom?

Answer 12

7

Group 7

Question 13

What is the charge for a chloride ion?

Answer 13

-1

Question 14

Why does chlorine atom form ions with a charge of -1?

Answer 14

• has 7 electrons in its outer shell
• gains 1 electron ( electrons are negative)

To get a full outer shell (noble gas configuration)

Question 15

Do simple molecules have high or low melting points?

Answer 15

Low

Question 16

What state do simple molecules exist in at room temperature?

Answer 16

Solids,liquids or gases

Question 17

Why do simple molecules have low melting and boiling points?

Answer 17

• weak forces
• between the molecules (intermolecular forces)
• so a small amount of energy needed to break those forces

Question 18

Why do simple molecules not conduct electricity?

Answer 18

No overall electrical charge

Question 19

Do ionic compounds have high or low melting points?

Answer 19

High

Question 20

Why do ionic compounds have high melting points?

Answer 20

• giant ionic lattice
• strong electrostatic forces
• between oppositely charged ions
• so lots of energy is needed to break lots of bonds

Question 21

Why do solid ionic compounds not conduct electricity?

Answer 21

Ions are not free to move

Question 22

If you melt or dissolve a solid ionic compound it will conduct electricity why?

Answer 22

• ions are free to move

- and carry the current (charge)

Question 23

Why do macromolecules have high melting points?

Answer 23

• giant covalent lattice

- all atoms are linked by strong covalent bonds

Question 24

Explain why diamond is so hard

Answer 24

Each carbon forms 4 strong covalent bonds with other carbons forming a giant covalent structure

Question 25

Explain why graphite is soft & slippery

Answer 25

Each carbon bonds to 3 other carbons through strong covalent bonds. - this forms layers which can slide over each other because of weak intermolecular forces between the layers

Question 26

Explain why graphite conducts electricity

Answer 26

1 electron on each carbon is delocalised | And can move through the whole structure

Question 27

What are some of the uses in fullerenes?

Answer 27

- drug delivery in the body - lubricants - catalyst - nanotubes for remforcing

Question 28

Describe the structure of fullerenes?

Answer 28

Macromolecules - made up of hexagonal rings of carbon atoms

Question 29

Explain why metals are good conductors of heat & electricity

Answer 29

- they contain de-localised electrons | - which can move though the whole structure

Question 30

Explain why metals can be easily bent and shaped?

Answer 30

-atoms are arranged in layers which can slide over each other

Question 31

What is an alloy

Answer 31

A mixture of a metal and another element (usually another metal)

Question 32

Why are alloys usually harder than pure metals?

Answer 32

Different atoms are different sizes therefore more difficult for layers to slide over each other.

Question 33

What is a shape memory alloy?

Answer 33

A material that returns to its original shape when deformed e.g Nitinol in dental braces

Question 34

How do you make low density poly ethane (ldpe)

Answer 34

- 200.c | - high pressure

Question 35

How do you make high density poly ethane (HDPE) ?

Answer 35

- lower temperature - lower pressure - use a catalyst

Question 36

Why do thermosotening polymers melt easily?

Answer 36

- individual tangled chains | - weak intermolecular forces between the chains

Question 37

Why do thermosetting polymers do not melt easily?

Answer 37

-individual chains are held together by cross/links (usually sting covalent bonds)

Question 38

What is a nano particle/nanoscience?

Answer 38

Structures that are 1-100nm ^ Nanometer

Question 39

What are the features of nano particles?

Answer 39

- different properties to the same material in bulk ( Color,strength etc) - high surface area to volume ratio

Question 40

What are some of the uses of nano science?

Answer 40

- computer equipment -light & strong - catalyst Materials - sensors - electrical - coatings Conductors - cosmetics - sun creams