period 3

Question 1

appearance and physical properties of sodium

Answer 1

metallic
shiny
worst conductor

Question 2

reaction of sodium with acid

Answer 2

Na + acid = H2 + salt

Question 3

reaction with sodium with cold water

Answer 3

vigorous reaction, floats, fizzes, melts
due to - delta H
NaOH ph 13-14
2Na + 2 H2O = 2NaOH + H2

Question 4

reaction of sodium with oxygen

Answer 4

bright yellow flame, forms white powder

2Na + 1/2O2 = Na2O

Question 5

appearance and physical properties of magnesium

Answer 5

metallic
shiny
conducts electricity

Question 6

reaction of Mg with cold water

Answer 6

very slow reaction
ph 10 Mg(OH)2
Mg + 2H2O = H2 + Mg(OH)2

Question 7

reaction of Mg with steam

Answer 7

Mg + H2O = MgO + H2

Question 8

reaction of Mg with oxygen

Answer 8

bright yellow flame, forms white powder

2Mg + O2 = 2MgO

Question 9

appearance and physical properties of aluminium

Answer 9

metallic
shiny
best conductor

Question 10

reaction of Al with cold water

Answer 10

no reaction

Question 11

reaction of Al with oxygen

Answer 11

bright flame
forms white powder
4Al + 3O2 = 2Al2O3

Question 12

why is Al considered unreactive

Answer 12

covered in Al2O3 which is unreactive

Question 13

appearance and physical properties of silicone

Answer 13

semimetal (metalloid)

semiconductor

Question 14

reaction of silicone with oxygen

Answer 14

Si + O2 = SiO2

Question 15

appearance and physical properties of phosphorus

Answer 15

non-metal 
low mp/bp
does not conduct
red as a crystal structure
white as P4

Question 16

reaction of phosphorous in excess oxygen

Answer 16

4P + 5O2 = P4O10

Question 17

reaction of phosphorous in limited oxygen

Answer 17

4P +3O2 = P4O6

Question 18

appearance and physical properties of sulfur

Answer 18

non metal
low mp/bp
does not conduct electricity

Question 19

reaction of sulfur with oxygen

Answer 19

colourless gas

S + O2 = SO2

Question 20

different types of structure and bonding by period 3 oxides

Answer 20

Na ionic lattice
ionic lattice
ionic lattice with covalent character
giant covalent
simple covalent
S simple covalent

Question 21

trend in melting point p3 oxides

Answer 21

increases along group fpr metals due to strong ionic bonding, Al2O3 is lower due to covalent character.
decreases with size for simple molecular molecules

Question 22

which p3 oxides are basic

Answer 22

Na2O

MgO

Question 23

Na oxide with water

Answer 23

Na2O + H2O = 2Na+ + 2OH-

Question 24

Mg oxide with water

Answer 24

MgO + H2O = Mg2+ + 2OH- = Mg(OH)2

Question 25

what are the products if Na2O and MgO react with acid

Answer 25

salt and water only

Question 26

is aluminium oxide acidic or basic

Answer 26

amphoteric

Question 27

aluminium oxide with HCl

Answer 27

Al2O3 + 6HCl = 3H2O + 2AlCl3

Question 28

aluminium oxide with NaOH

Answer 28

Al2O3 + 2NaOH + 3H2O = 2NaAl(OH)4

Question 29

in what conditions will silicon dioxide act as an acid

Answer 29

reacts as a weak acid in a strong base

Question 30

silicon dioxide with hot conc NaOH

Answer 30

SiO2 + 2NaOH = H2) + Na2SiO3

Question 31

phosphorous pentoxide with water

Answer 31

P4O10 +6H2O = 4H3PO4

Question 32

SO2 with water

Answer 32

SO2 + H2O = H2SO3

Question 33

SO3 with water

Answer 33

SO3 + H2O = H2SO4

Question 34

SO2 with NaOH

Answer 34

SO2 + NaOH = NaHSO3

NaHSO3 + NaOH = Na2SO3 + H2O

Question 35

shape and bonding in PO4 3-

Answer 35

tetrahedral structure 109.5 bond angle

Question 36

shape and bonding in SO4 2-

Answer 36

tetrahedral with 109.5 bond angle

Question 37

shape and bonding in SO3 2-

Answer 37

106 bond angle

trigonal pyramid

Question 38

uses of MgO

Answer 38

additive for cattle feed

Question 39

uses of SO2

Answer 39

reactant in contact process