topic 2 (bonding,structure...)

Question 1

properties of ionic compounds

Answer 1

high melting and boiling points(strong electrostatic force of attraction)

cannot conduct electricity when solid (as ions cannot move )

Question 2

allotropes

Answer 2

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

Question 3

allotropes of carbon

Answer 3

diamond= is very hard ,does not conduct electricity and has a high melting point

graphite= is soft and slippery with a high melting point

graphine= is one layer of graphite

fullerenes =hollow balls of carbon

Question 4

ionic compounds

Answer 4

many ionic form crystals ,ionic compounds form giant compounds and are 3 dimensional

Question 5

states of matter

Answer 5

solid
liquid
gas

Question 6

changing of state

Answer 6

solid
melting (down) freezing (up)
liquid
boiling (down) condensing (up)
gas

Question 7

nanoparticles

Answer 7

A nanoparticle or ultrafine particle is usually defined as a particle of matter that is between 1 and 100 nanometres in diameter

uses: transparent sunglasses,coating for solar cells,self cleaning windows……
effects: this effects of inhaled nanoparticles are inflammation and heart problems

Question 8

polymers

Answer 8

a polymers is a substance which has a molecular structure built up chiefly or completely from a large number of similar units bonded together, all atoms in a polymer are joined by covalent bonds

Question 9

giant covalent structures

Answer 9

giant covalent structures are macromolecules (a molecule containing a very large number of atoms)
and these are joined together by strong covalent bonds

Question 10

ionic bonds

Answer 10

attraction between a metal and a non-metal
the metal gives away its electron (and is a positive ion)
the non-metal gains electrons (and becomes a negative ion)

Question 11

covalent bond

Answer 11

the attraction between two non-metals which share electrons

Question 12

metallic bonding

Answer 12

is a type of bonding produced by electrostatic force of attraction between electrons and positive ions

Question 13

properties of covalent bonds (molecules)

Answer 13

small covalent molecules have low melting and boiling points (meaning they’re usually liquids or gases at room temperature )

they also do not conduct electricity (as they have no overall charge)