3.3 Chemistry of the p-Block Flashcards
What does amphoteric mean?
A compound with both basic and acidic properties
What shape is the P orbital?
Dumbell
Why can PCl5 exist but not NCl5?
As nitrogen has no available D-orbitals and therefore cannot expand the octet
How does PCl5 exist?
Phosphorous has D orbitals, electrons can unpair and jump allowing 5 covalent bonds to form with 10 electrons in its outer shell
What is a general rule for the expanding the octet?
If there is space in the d orbital, the number of outer electrons is the number of covalent bonds formed
Why is BF3 called electron deficient?
As it the Boron only has 6 electron in the outer shell
What energy type is bond making?
Exothermic
What energy type is bond breaking?
Endothermic
2AlCl3 —->
Al2Cl6
Why does 2AlCl3 go to Al2Cl6?
As the lone pairs on the chlorine forms coordinate bonds with the Aluminium
Name 2 amphoteric ions?
Al 3+
Pb 2+
How do Aluminium and lead react as bases?
By forming salt and water
How do you identify an amphoteric compound?
Adding NaOH it will from a white precipitate that re dissolves in excess NaOH
What are the properties of diamond? (5)
Hard, high melting point, forms 4 covalent bonds, conducts heat, does not conduct electricity
What are the properties of Graphite? (5)
Soft, 3 covalent bonds, conducts heat, high melting point, conducts electricity
What does Isoelectronic mean?
A compound with the same number of electrons in its outer shell as another
What does allotrope mean?
A different form of the same element
Name an isoelectronic compound to diamond and graphite?
Cubic B-N and Hexagonal B-N
What does Immiscible mean?
Does not mix
How does Carbon chloride react with water? + observation
Does not react (due to no d orbitals in carbon) but forms layers with CCl4 on top
How does silicon chloride react with water? + observation
forms SiO2 or SI(OH)4 and HCl
a white precipitate and misty fumes are observed
How does lead chloride react with cold water? + observation
No reaction
white solid (lead) in water
How does lead chloride react with hot water? + observation
Sparingly soluble
colourless solution with white ppt
What colour is PbI2?
Canary yellow ppt
What is the inert pair effect?
The trend of stability of oxidation states and the unsharring of the outer s-orbital electrons (an inert pair)
What is the inert pair effect?
The trend of stability of oxidation states and the unsharring of the outer s-orbital electrons (an inert pair)
What is the trend of the inert pair effect?
+4 more stable at top of group
+2 more stable at bottom of the group
What is the trend of electronegativity in group 7?
Electronegativity decreases down the group
What is a disproportionation reaction?
Where an element is both reduced and oxidised in the same reaction
What is HClO used for? (and its name?)
Chlorate (I) acid kills bacteria in pools
What is NaClO used for? (and its name?)
Sodium chlorate (I) is bleach
What is NaClO3 used for? (and its name?)
Sodium chlorate (V) is weed killer
What does an oxidising agent do?
Gains electrons
What does a reducing agent do?
Looses electrons
What does a reducing agent do?
Looses electrons
What does NaBr/Cl/I + H2SO4 do?
Forms NaHSO4 + HCl/Br/I with misty fumes
What does HBr + H2SO4 do?
Br2 (orange yellow solution) + SO2 (choking gas) + H2O
What does HI + H2SO4 do?
I2 ( orange brown solution) + H2S (rotten egg smell) and H2O
What does sublimation mean?
Move from solid to gas
What colour is I2 solid and gas
solid- grey
gas - purple
