Chapter 3

Question 1

what are ions?

Answer 1

charged particles

Question 2

How are ions made?

Answer 2

when an atom looses or gains an electron

Question 3

metal atoms lose electrons to form __________ ions?

Answer 3

positive

Question 4

Non-metal atoms gain electrons to form __________ ions?

Answer 4

negative

Question 5

why are ions formed?

Answer 5

so atoms can get full outer shells

Question 6

what is the group number the same as?

Answer 6

the number of outer shell electrons an atom has

Question 7

what is ionic bonding?

Answer 7

electrostatic attraction between oppositely charged ions (metal and non-metals)

Question 8

how would you describe the ionic bonding between atoms?

Answer 8

__________ (metal) has lost __ (number) electron/s. _________ (non-metal) has gained __ (number) electron/s. __________ (metal) gets a ___ charge and _________ (non-metal) gets a ____ charge, both have full outer shells and our held together by an electrostatic attraction

Question 9

what charge do all ionic compounds have?

Answer 9

neutral

Question 10

what do substances with strong ionic bonds have?

Answer 10

high melting and boiling points and can be dissolved easily in water

Question 11

For a substance to conduct electricity it must have what?

Answer 11

charged free moving atoms or ions

Question 12

what structure do ionic compounds form?

Answer 12

giant ionic lattice

Question 13

can ionic compounds conduct electricity?

Answer 13

solid - no
molten or dissolved - yes

Question 14

what are the disadvantages to ball and stick models to show the structure of ionic compounds?

Answer 14

ions aren’t always shown to scale, they suggest there are gaps between ions

Question 15

what are the properties of simple covalent molecules?

Answer 15

low melting and boiling points - weak intermolecular forces that do not require much energy to break

Question 16

what is covalent bonding?

Answer 16

formed when a pair of electrons is shared between two atoms, between two non-metals

Question 17

how can you find the molecular formula of a covalent bond?

Answer 17

count up how many atoms of each element there are in a diagram of the molecule

Question 18

the two electrons that are shared have _________ attraction to both ________ so have a __________ bond holding them together

Answer 18

equal, nuclei, very strong

Question 19

what are simple molecules made of?

Answer 19

only a few atoms joined by covalent bonds

Question 20

do simple covalent molecules conduct electricity?

Answer 20

no

Question 21

what are allotropes?

Answer 21

different structural forms of the same element in the same physical state

Question 22

what is a polymer?

Answer 22

lots of long molecules made up of repeating sections, all the atoms in a polymer molecule are held together by strong covalent bonds

Question 23

what is the difference between giant covalent molecule (macromolecules) and giant ionic structures (lattices)?

Answer 23

macromolecules have no charged ions

Question 24

examples of giant covalent molecules (macromolecules)?

Answer 24

silicon dioxide, diamond and graphite

Question 25

True/False, giant covalent structures have high melting and boiling points?

Answer 25

true

Question 26

in diamond, each carbon atom forms _______ covalent bonds with other carbon atoms causing a very rigid structure

Answer 26

four

Question 27

properties of diamond?

Answer 27

very strong - four covalent bonds, forms a tetrahedral structure) very high melting and boiling points - strong covalent bonds take lots of energy to overcome, MP is about 4000°C. doesn't conduct electricity - no free moving electrons

Question 28

in graphite, each carbon atoms only forms ________ covalent bonds, creating sheets of carbon arranged in hexagons?

Answer 28

three

Question 29

how is graphite held together?

Answer 29

weak intermolecular forces

Question 30

whats graphite ideal for?

Answer 30

lubricating material

Question 31

what are the properties of graphite?

Answer 31

high melting point- covalent bonds in the layers take lots of energy to break, about 3800°C. graphite conducts electricity and thermal energy- there is one delocalised electron per carbon atom

Question 32

what is graphene?

Answer 32

a sheet of carbon atoms joined together in hexagons, single layer of graphite, one atom thick making it a 2D substance

Question 33

what makes graphene very strong?

Answer 33

network of covalent bonds

Question 34

why is graphene added to composite materials?

Answer 34

its incredibly light and improve materials strength without adding much weight

Question 35

can graphene conduct electricity?

Answer 35

yes, they have a delocalised electron and has the potential to be used in electronics

Question 36

what are fullerines?

Answer 36

hollow molecules of carbon shaped like tubes or balls

Question 37

what was the first fullerine discovered?

Answer 37

buckminsterfullerine, with a molecular formula of C60, forms a hollow sphere containing 20 hexagons and 12 pentagons

Question 38

what are nanotubes?

Answer 38

fullerines which are tiny carbon cylinders?

Question 39

what are the uses of fullerines?

Answer 39

in medicine, as catalysts, as lubricants, strengthening materials, in electronics

Question 40

how are atoms in a metal arranged?

Answer 40

in a regular pattern

Question 41

properties of metals?

Answer 41

high melting and boiling points - the electrostatic forces between the metal atoms and the delocalised sea of electrons are very strong conduct electricity - delocalised electrons are free to move through the whole structure malleable - atoms form layers that are able to slide over one another

Question 42

what happens when another element is mixed with a pure metal?

Answer 42

the new elements atoms will distort the layers, making it harder for them to side over each other and , makes the metal stronger