bonding, structure and the properties of matter

Question 1

what substance can be sublime?

Answer 1

solid carbon dioxide (dry ice)

Question 2

what happens during change of state?

Answer 2

during the changes particles gain energy which is used to break bonds between particles.

Question 3

what is a solid?

Answer 3

solid is a fixed shape and cannot flow, they cannot be compressed as they have no space to move into

Question 4

what is a liquid?

Answer 4

liquids flow and take the shape of their container, their particles can move around each other but cannot be compressed

Question 5

what is a gas?

Answer 5

gases flow and completely fill the container, the particles can move quickly and can be compressed

Question 6

what does the amount of energy needed to change state depend on?

Answer 6

the strength of the forces between the particles

Question 7

what is the negative electrode?

Answer 7

cathode

Question 8

what is the positive electrode?

Answer 8

anode

Question 9

what is the negative ion?

Answer 9

anion

Question 10

what is the positive ion?

Answer 10

cation

Question 11

what is used to lower the boiling point up in electrolysis?

Answer 11

cryolite

Question 12

what is produced at the cathode? (negative electrode)

Answer 12

hydrogen is produced if the metal is more reactive than hydrogen

Question 13

what is produced at the anode? (positive electrode)

Answer 13

oxygen is produced unless the solution contains halide ions when the halogen is produced

Question 14

what happens to the melting and boiling point of substances?

Answer 14

the stronger the forces between particles, the higher its melting and boiling points

Question 15

what process is condensing and freezing?

Answer 15

exothermic

Question 16

what process is melting, evaporating and boiling?

Answer 16

endothermic

Question 17

what happens to the forces of attraction during condensing and freezing?

Answer 17

they get stronger

Question 18

if the given temperature is lower than the melting point what will the predicted state be?

Answer 18

solid

Question 19

if the given temperature is between melting and boiling point, what will the predicted state be?

Answer 19

liquid

Question 20

if the given temperature is bigger than the boiling point, what will the predicted state be?

Answer 20

gas

Question 21

how are ions formed?

Answer 21

by the transfer of electrons

Question 22

what pattern is an ionic compound?

Answer 22

the lattice is a regular pattern with oppositely charged ions next to each other

Question 23

what is an ionic lattice held together by?

Answer 23

strong electrostatic forces of attraction between oppositely charged ions

Question 24

what do ionic compounds have?

Answer 24

high melting and boiling points, they are in the solid state at room temperature

Question 25

when can a substance conduct electricity?

Answer 25

if it contains charged particles, such as ions and these particles are free to move

Question 26

when can an ionic compound conduct electricity?

Answer 26

when it has melted to form a liquid or it has dissolved in water to form an aqueous solution

Question 27

what are ionic compounds when solid?

Answer 27

insulators

Question 28

what is a covalent bond? and when does it occur?

Answer 28

formed when two atoms share a pair of electrons. it occurs in most non-metal elements and in compounds formed between non-metals

Question 29

what is a molecule?

Answer 29

a group of two or more atoms joined together by covalent bonds.

Question 30

what size is a water molecule?

Answer 30

0.3 nm (3x10- 10m)

Question 31

what size is a water molecule?

Answer 31

0.3 nm (3x10- 10m)

Question 32

give one advantage and one disadvantage of using a dot and cross diagram

Answer 32

•advantage- shows the pairs of outer electrons and which atoms they have come from •disadvantage- it does not show how the atoms are arranged in space

Question 33

give one advantage and one disadvantage of using a dot and cross diagram

Answer 33

•advantage- shows the pairs of outer electrons and which atoms they have come from •disadvantage- it does not show how the atoms are arranged in space

Question 34

give the structure of an oxygen molecule, using one line to represent each shared pair of electrons

Answer 34

O=O

Question 35

what do most substances with simple molecules have?

Answer 35

low melting and boiling points