Perdiocity

Question 0

What is the trend in
Electrical conductivity?
Melting and boiling point?

Answer 0

Na-Al increases due to increase in delocalised e-s&decreasing radius
Si-steep decrease change in structure no delocalised e-s

Na-Al
Increases metallic bonding due to increased delocalised electrons and decreasing radius
Al-Si
Increase change in structure to giant covalent strong cov bonds
Si-P
Decreases from giant cov to simple cov
P4-S8-Cl2
increases then decreases based on vdw and size of molecule
Cl-Ar
Decreases molecular to atomic

Question 1

What is the trend in
Atomic radius
First ionisation radius (2 discontinuities)
Electronegativity

Answer 1

Decreases- increases nuclear attraction for the same shielding
Increases
Al-in 3p sub shell more shielded from nucleus
S- spin pair repel
Increases-increased nuclear attraction same shielding

Question 2

Which 3 elements react with water?

What is the equation for 
Sodium with water 
The ionic version 
Magnesium with cold water 
Magnesium with steam 
Chlorine with water 

How does sodium react with water?
How does magnesium react with cold water?

Answer 2

Na Mg Cl2

2Na(s)+ 2H2O(l) --> 2NaOH(aq) + H2(g)
2Na(s)+2H2O(l) --> 2Na+(aq)+2OH-(aq)+H2(g)
Mg(s)+2H2O(l)--> Mg(OH)2(aq)+H2(g)
Mg(s)+H2O(l)-->MgO(s)+H2(g)
Cl2(g)+H2O(l) --> HCl(aq)+HClO(aq)

Vigorously
Slowly

Question 3

Reactions with O2 
Which elements burn in air?
What does sodium burn with?
What's the equation?
What do Mg,Al,Si and P burn with?
What are the equations for this?
What does S burn with?
What's the equation for this?

Answer 3

The solid ones 
2Na(s)+1/2O2(g)-->Na2O(s)
Bright white flame and white smoke
Mg(s)+1/2O2--> MgO(s)
2Al(s)+3/2O2-->Al2O3(s)
Si(s)+O2(g)-->SiO2(s)
P4(s)+5O2(g)-->P4O10(s)
Blue flame and choking sulphur dioxide 
S(s)+O2(g)-->SO2(g)

Question 4

Which oxides are giant covalent?
Which are giant ionic?
Which are simple covalent?
Which have high melting points and why?
Which have low melting points and why?

Answer 4

SiO2
Na2O MgO Al2O3
P4O10 SO2 SO3
Giant covalent and ionic because there are strong intermolecular forces between ions and atoms
Simple covalent bc have strong forces within molecules but weak intermolecular forces

Question 5

Reaction of the oxides with water
  Which oxides are insoluble?
  What is the structure,pH and an equation of the oxide with water
  Na2O
  MgO
  P4O10
  SO2
  SO3

Answer 5

Al2O3 and SiO2
Ionic 14 
  Na2O(s)+H2O(l)-->2NaOH(aq)
Ionic 9 
  MgO(s)+H2O(l)-->Mg(OH)2(aq)
Simple cov 0
  P4O10(s)+6H2O(l)-->4H3PO4(aq)
Simple cov 3 
  SO2(g)+H2O(l)-->H2SO3(aq)
Simple cov 0 
  SO3(g)+H2O(l)-->H2SO4(aq)

Question 6

What does amphoteric mean?
Which oxide is amphoteric?

Equation for reaction of
Na2O MgO Al2O3
with HCl
THESE ARE

Equation for reaction
Al2O3 SiO2 P4O10 SO2 SO3
with NaOH
THESE ARE

Answer 6

Reacts with acids and bases
Al2O3

Na2O(s)+HCl(aq)–>2NaCl(aq)+H2O(l)
MgO(s)+HCl(aq)–>MgCl2(aq)+H2O(l)
Al2O3(s)+6HCl(aq)–>2AlCl3(aq)+3H2O(l)
Bases

Al2O3(s)+6NaOH(aq)+3H2O(l)-->2NaAl(OH)4(aq)
SiO2(s)+2NaOH(aq)-->NaSiO3(aq)+H2O(l)
H3PO4(aq)+3NaOH(aq)-->Na3PO4(aq)+3H2O(l)
SO2(aq)+2NaOH(aq)-->Na2SO3(aq)+H2O(l)
SO3(aq)+2NaOH(aq)-->Na2SO4(aq)+H2O(l)
Acid

Question 7

What is observed when Mg heated with water in the absence of air?

Answer 7

White powder

Bright white flame

Question 8

What does higher charge on metal ion cause?

Answer 8

Stronger attraction to the delocalised sea of electrons

Question 9

What’s are physical properties of giant covalent molecules?(4)

Answer 9

Non conductors
Hard
Brittle
Insoluble

Question 10

What is sulphur (IV) oxide?

Reaction with water to form ions

Answer 10

SO2

SO2+H2O>H+ +HSO3-