Chemical Bonding: Metallic Bonding Flashcards Preview

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Flashcards in Chemical Bonding: Metallic Bonding Deck (25):
1

what is metallic bonding?

attraction between the ‘sea of delocalised electrons’ and the positive ions

2

which groups are involved?

occurs between metals (group 1,2,3 and transition metals)

3

how does it work?

the metal loses its outer shell electron(s) to form the positive metal ion

electrons are delocalised into the space between the positive metal ions - this is the ‘sea of delocalised electrons’

delocalised electrons are free to move

 

4

can metallicly bonded substances conduct electricity and heat? why?

yes

delocalised electrons are free to move

5

what is an alloy?

mixture of metals (two or more)

6

what are some examples of alloys?

 brass = copper and zinc

steel = iron, zinc and carbon

7

how can metals be made harder?

by alloying them

(this is the main purpose of alloys)

8

are atoms in alloys different sizes or the same?

different

9

what happens as a result of atoms in alloys being different sizes?

this disrupts regular packaging

makes it difficult for particles to slide over each other when a force is applies

10

what are some uses of copper?

sauce pans

water pipes

electrical wires

door handles

power lines

11

what are some examples of alloys' uses?

coins

furniture

car wheels

ships

buildings

12

what structure do metallic bonds form?

giant metallic structure

13

what is the giant metallic structure

 Regular array of positive ions and ‘sea of delocalised electrons’

held together by the attraction between the two

14

do metals tend to be strong or weak? high or low melting and boiling points?

why?

strong

high

 because of the powerful attractions between them

15

are metals good or bad conductors of electricity? why?

good

because the delocalised electrons are free to move through the structure

16

are metals good or bad conductors of heat? why?

good

 because delocalised electrons are free to move

if you heat one piece of metal, the energy is picked up by the electrons

as they electrons move, the heat energy is transferred throughout the structure

17

how do metals conduct electricity?

18

which metal is used as a coating to prevent rusting and which property does the use depend?

zinc

more reactive than object it is covering

19

which metal is used as an aircraft body and which property does the use depend?

aluminium

to be strong

20

which metal is used as electrical wiring and which property does the use depend?

copper

to be bent into shape easily

conducts electricity

sacrificaial protection

21

which metal is used as railway tracks and which property does the use depend?

steel

ability to expand

very strong

22

what are some metals described as being? what does this mean?

elastic

this is when, if it is subject to a small force, it will stretch and then return back to its original shape when the force is released

if a large force is applied, the particles slide over each other and stay in their new positions

23

are metals usually bent into shape easily or with difficulty? why?

easily

because their layers slide easily over each other

 

24

what does malleable mean?

easily beaten into shape

 

25

what does ductile mean?

easily pulled into wires