A1

Question 1

define acid

Answer 1

substances that dissociates in water to form h+ ions

Question 2

give an example of an acid

Answer 2

HCL—> H+ + CL-

Question 3

define base

Answer 3

substances that react with acids to form water and salt

Question 4

define alkali

Answer 4

a base that dissolves in water to form OH- ions

Question 5

define amphoteric

Answer 5

substances that can act as both acid and base

Question 6

what is the chemical equation for aluminium oxide?

Answer 6

AL2O3

Question 7

is alumina chemically inert?

Answer 7

yes it is, however under some conditions it is not, for example it can react with hot bases and acids

Question 8

is alumina amphoteric? and why

Answer 8

yes because it can react with hot bases and acids only

Question 9

what are some of the uses of alumina?

Answer 9

since it is chemically inert, can be used for filler, paint, sunscreen and glass

it is also an effective desiccant.

Question 10

what ion does an element become if it loses an electron?

Answer 10

postive ion

Question 11

what ion does an element become if it gains an electron?

Answer 11

negative ion

Question 12

what is the equation of alumina acting as a base?

Answer 12

AL2O3+6HCL—> 2ALCL3+3H20

Question 13

what is the equation for alumina acting as a acid?

Answer 13

AL2O3+6NaOH+3H2O—>2Na2AL(OH)6

Question 14

how are salts formed?

Answer 14

salts are formed when h+ ions in acids are replaced with another positive ion. this is usually with either a metal ion or ammonium.

Question 15

what is the chemical formula of ammonium?

Answer 15

NH4+

Question 16

what are metal oxides?

Answer 16

metal oxides are bases. bases react with acids to form salt and water.

Question 17

what is the equation of metal oxides?

Answer 17

metal oxides+ acid–> salt+ water

Question 18

give an example of metal oxide.

Answer 18

CaO+2HCI–> CaCl2+H20

Question 19

what are metal hydroxides?

Answer 19

they’re alkalis. alkali is a base dissolving in water to form OH- ions.

Question 20

what is the equation of metal hydroxides?

Answer 20

metal hydroxides+ acid–> salt + water

Question 21

what do metals form?

Answer 21

positive ions

Question 22

what do non metals form?

Answer 22

negative ions or none sometimes

Question 23

why are metals more reactive down the periodic table?

Answer 23

because the outermost shell is far from the nucleus.

Question 24

what bonding do metals have?

Answer 24

they have metallic bonding

Question 25

what are some properties of metals?

Answer 25

they're: - malleable -great conductors of heat -high mp&bp -shiny -sonorous( make sound)

Question 26

properties of non metals

Answer 26

-poor conductivity -low mp&bp -brittle -low density -dull most of them are gaseous

Question 27

what is meant by effluent?

Answer 27

liquid waste that is discharged into a river or stream

Question 28

what happens when factories use sulfuric acid?

Answer 28

it can make the effluent acidic, which can lower the pH of the water, damaging the environment.

Question 29

what can you do to increase the pH?

Answer 29

bases can react with acids such as calcium hydroxide, which will form salt and water, neutralising the pH of the water.

Question 30

what is the chemical equation of calcium hydroxide?

Answer 30

Ca(OH)2+H2S04--> CaSo4+2H20

Question 31

what is meant by refractory material?

Answer 31

Refractory material is material that is physically and chemically stable at very high temperatures

Question 32

how is alumina a refractory material? and what is it used for?

Answer 32

it maintains its strengths at high temps and its chemically and physically stable. its an excellent material to be used inside furnaces and reactors.

Question 33

why are transition metals and compounds useful catalysts within industries?

Answer 33

allow reactions to take place at lower temperatures: which reduces the amount of energy needed in industries and reduces costs of production. they also provide alternative reaction pathways with lower activational energy.

Question 34

what are catalysts?

Answer 34

substances that increase rate of reaction

Question 35

what is activation energy?

Answer 35

the minimum amount of energy needed between colliding particles to have a successful collision to take place.