Nitrogen and Group 5
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Transcript of Nitrogen and Group 5
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P block group V 1
The P BlockThe P BlockNitrogen and Group 5
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P block group V 2
Group 5Group 5 Is at the centre of the periodictable
Top of group, non-metals: Nitrogen and Phosphorus
Bottom of group, metalloids
(metallic elements with non-metalcharacter): Antimony and Bismuth
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P block group V 3
14.0
N Nitrogen [He] 2s2
2p3
7
31.0
P Phosphorus [Ne] 3s23p315
74.9
As Arsenic [Ar] 3d104s24p333
121.8
SbA
ntimony [Kr]4d10
5s2
5p3
51
209.0
Bi Bismuth [Xe] 4f145d106s26p
383
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P block group V 4
Group 5Group 5 Group 5 elements can form 3 covalent
bonds
Sharing the 3 unpaired electrons Gives compounds with oxidation state of +3
or 3 for group 5 element
Each atom has a lone pair of electrons
Enables
atoms
to form dative covalent bonds
When they do this Group 5 elements canform some compounds with oxidation state of+5 for the Group 5 element
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P block group V 5
NitrogenNitrogen Very abundant element Very unreactive! N2 unreactive because of strong triple
bond holding Ns together Bond enthalpy of N N is +945 kJ mol-1
(Bond enthalpy of N-N is +158 kJ mol-1)
Hence most reaction of N2 have high EA andrequire high T and catalysts to make themoccur Haber process- high T + Fe catalyst. Lightning or >2000C to make N2 react with O2
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P block group V 6
AmmoniaAmmonia Ammonia is nitrogenhydride, NH3
Lone pair notinvolved in bonding Dative covalent
bonds (dcbs)possible
N HH
H
..
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P block group V 7
AmmoniaAmmonia
NH3 is a base andforms dcbs to H+ ionsto give ammonium ions
(NH4+) Remember once dcbs
formed no different fromcbs!
NH3 also form
sdcb
swith TM ions and is a
good ligand in complexes(see earlier!!)
+
N HH
H
H
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P block group V 8
Nitrogen Oxides
Nitrogen Oxides
Name /Name /FormulaFormula
AppearanceAppearance Where it comesWhere it comesfromfrom
Nitrogenmonoxide
NO
Colourlessgas, turnsto brownNO2 in air
Combustionprocesses
Thunderstorms
Formed in thesoilby denitrifying
bacteria
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P block group V 9
Nitrogen Oxides
Nitrogen Oxides
Name /Name /FormulaFormula
AppearanceAppearance Where it comesWhere it comesfromfrom
Nitrogendioxide
NO2
Brown gas(toxic)
From oxidation ofNO in theatmosphere
Dinitrogenoxide
N2O
Colourle
ssgas
Formed in thesoilby denitrifying
bacteria
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P block group V 10
Nitrates
Nitrates
2 Kinds of nitrate ions involved inthe nitrogen cycle: Nitrate(III), NO2
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Nitrate(V), NO3-
Both are called nitrates, but
distinguished by showing OS of N
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P block group V 11
Bonding in NitratesBonding in Nitrates
O
O
NO
-
By using its lone pair to
a dative covalent bondto an oxygen atom,thenitrogen increases itsoxidation state to +5
Nitrate(V)
The charge is
delocalised over thetwo N-O bonds, which
are equivalent
Nitrate(III)
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N OO
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P block group V 12
NitratesNitratesName andFormula
Commonlycalled
Properties
Nitrate(V) ion
NO3-
Nitrate Oxidising agent
Metal nitrate(V)compounds are verysoluble in water
Nitrate(III) ion
NO2-Nitrite Can be reducing or
oxidising agent Metal nitrate(III)compounds aresoluble in water