The Elements of Group 5a the Nitrogen Family

p-Block ELEMENTS – NITROGEN Family unit

GENERAL CHARACTERISTICS

The group xv of the periodic table consists of nitrogen, phosphorous, arsenic, antimony and bismuth. These elements are known as pnicogens and their compounds as pnicomides .

ELECTRONIC CONFIGURATION

Element	At. No.	Electronic configuration	Valence vanquish
Nitrogen	7	[He] 2s 2 2p 3	2s 2 2p three
Phosphorous	15	[Ne] 3s 2 , 3p 3	3s 2 3p three
Arsenic	33	[Ar] 3d 10 , 4s ii 4p 3	4s 2 4p 3
Antimony	51	[Kr] 4d 10 , 5s 2 5p 3	5s 2 5p 3
Bismuth	83	[Xe] 4f 14 , 5d ten 6s 2 6p iii	6s ii 6p iii

Metal CHARACTER

N, P(non metals), Equally, Sb(metalloids), Bi(metal)

PHYSICAL STATE

Nitrogen is showtime element subsequently hydrogen to be a diatomic gas in normal class. All other elements in the grouping are ordinarily solids.

ATOMICITY

N 2 is diatomic while others are tetra-diminutive M 4

MELTING AND Humid POINTS

The melting point increases from nitrogen to arsenic. The boiling points increase regularly on moving downwards the group.

DENSITY

Density increases downwardly the grouping.

Atomic RADII

Diminutive radii increases with increment in diminutive number.

COVALENT RADII

Covalent radii increases in a regular fashion downwardly the group.

ALLOTROPY

All the elements (except bismuth) show allotropy.

Nitrogen – a-nitrogen, b-nitrogen

Phosphorus – white, Red, blood-red, violet, a-black, b-black

Arsenic – Grey, Xanthous, Black

Antimony – Metallic, Xanthous, Explosive

OXIDATION STATE

N	P	Equally	Sb	Bi
–iii to +five	–3, +three, +four, +5	+iii, +5	+iii, +five	+3, +5

Nitrogen has a broad range of oxidation states

Oxidation state	Example
+5	N 2 O 5 , HNO three ,
+4	NO ii , N two O 4
+three	HNO 2 , , NF iii
+2	NO
0	N ii
–1	NH 2 OH, NH ii F
–2	N ii H four
–3	NH 3 , ,

NEGATIVE OXIDATION STATES

–3 oxidation state is exhibited by other elements also. Ca 3 P ii , Na 3 As, Zn iii Sb two

INERT PAIR EFFECT

Inert pair effect increases downwardly the group and due to this effect, the stability of +3 oxidation state increases and stability of +v oxidation state decreases on moving downwardly the group.

IONISATION ENERGY

Ionisation free energy of nitrogen is very loftier due to modest atomic radius. The ionisation free energy decreases down the group.

ELECTRONEGATIVITY

The electronegativity decreases from nitrogen to bismuth.

CATENATION

They exhibit the property of catenation but due to weak Thousand–M bond to less extent than 14 group elements.

Bond C–C Northward–North P–P As–As

kJ/mol 353.3 163.seven 201.six 147.iv

REACTIVITY

Elemental nitrogen is highly unreactive largely because of its potent triple bond. (almost as inert as noble gases).

While phosphorus is extremely reactive and kept in water. It is inflammable and can be ignited at 45ºC. It shows greenish luminescence or glow in dark on account of its tedious oxidation. This glow phenomenon is known as phosphorescence.

MULTIPLE BOND FORMATION

Only nitrogen has a trend to grade pp—pp multiple bonds. Others forms dp–pp multiple bonds easily.

COMPOUNDS OF GROUP fifteen ELEMENTS

HYDRIDES

All the elements of this group grade hydrides of the type MH iii which are covalent and pyramidal in shape.

Some properties follow the lodge which are

NH 3 > PH 3 >          AsH 3 >    SbH 3 >  BiH three

Ammonia    Phosphine   Arsine Stabene   Bismuthene

• Ease of germination

• Stability

• Basic character

• Solubility

• Bond angle (NH 3 107.5º ; PH iii 92º, AsH 3 91, SbH 3 90º)

• Strength of Yard – H bail

• Dipole moment

• Decomposition temperature

Some properties follow the order

NH three < PH 3 < AsH 3 < SbH 3 < BiH 3

• Reducing character

• Covalent character

• Poisonous character

• Charge per unit of combustion

Boiling points : BiH iii > SbH 3 > NH 3 > AsH iii > PH iii

PREPARATION OF HYDRIDES

Some hydrides  can exist prepared as follows :

1. Ammonia

   1. Any ammonium table salt + metallic oxide or hydroxide NH 3

eg.

or (NH 4 ) 3 PO four , NH iv NO 3 , (NH 4 ) 2 So 4 ,

(NH iv ) ii So 3 , (NH four ) ii S or (NH iv ) 2 (C 2 O four )

2. 2. 

2. Phosphine

3. Other hydrides

, M = As, Sb, Bi

HALIDES

All the elements of this group grade trihalides of the type MX three and except nitrogen all course pentahalides of the type MX 5

MX iii M = Northward, P, Every bit, Sb, Bi and X = F, Cl, Br or I

MX 5 when Ten = F, 1000 can be P, Equally, Sb and Bi
when X = Cl, G can be P, As and Sb

when Ten = Br, M can be P

NF 3 is a colourless, odourless gas and the nearly stable of this series. Information technology has low reactivity.

NCl three is a yellow oily liquid that reacts with h2o to form ammonia and hypochlorous acid.

NI 3 is shock sensitive and decomposes explosively when touched.

HYDROLYSIS

• Ease of hydrolysis BiCl 3 > SbCl iii > AsCl three > PCl 3 > NCl 3

• Trihalides except BiF three are covalent in nature

• Trihalides take pyramidal structure.

PENTAHALIDES

As nitrogen does not contain-vacant d-orbitals in the second shell and cannot expand its outer trounce hence information technology does not form pentahalides.

• The hybridisation in pentahalides is sp 3 d (trigonal bipyramidal)

• Thermally less stable than trihalides

• Deed as Lewis acids

• On complete hydrolysis they produce acids

OXIDES

All the elements of this grouping form oxides of the blazon 1000 ii O 3 and M two O 5 . either by direct combination with O ii or indirectly.

Oxides of N

Oxides of P

Oxides of Every bit

Oxides of Sb

Oxides of Bi

Due north ii O (DINITROGEN OXIDE OR NITROUS OXIDE) known as laughing gas

Grooming :

• Priestley's method :

• Bertholet's (mutual method) :

• 

Properties :

Colourless, fairly unreactive, pleasing odour, sweet taste, supports combustion. It is neutral.

Structure : Linear

Uses : Mixed with oxygen it is used as anaesthetic

NO (NITROGEN OXIDE OR NITRIC OXIDE)

Grooming :

• (mutual method)

• (commercial)

• (Lab method)

• (Ostwald's process)

Backdrop : Colourless, paramagnetic, slightly toxic gas, blueish in liquid state. It is combustible and supports combustion. It is neutral.

Information technology is reducing as well as oxidising in nature.

Uses :

i) For manufacturing of nitric acrid

ii) For detection of Oxygen

iii) For manufacturing of sulphuric acid as catalyst (Lead chamber procedure)

Structure :

NO 2 (NITROGEN DIOXIDE)

Preparation :

• 

• (Mutual method)

• 

Backdrop :
Highly toxic, paramagnetic, reddish brown gas with choking scent, acidic

Reactions :

• (Hence it is mixed anhydride of HNO ii and HNO 3 )

• 

• 

• It is combustible and supports the combustion of burning P, Mg or charcoal. Called-for South or candle is extinguished.

• It is oxidising and reducing in nature

Uses :

• For Manufacturing of HNO 3

• As Catalyst in lead chamber process for Sulphuric acid

Structure :

Due north 2 O 3 (DINITROGEN TRIOXIDE) NITROGEN SESQUIOXIDE

Preparation :

• 

• (common method)

Properties : It is blue solid, acidic

Hence information technology is anhydride of HNO 2

Absorbed past sulphuric acid

Structure : Shape and structure is not definitely known

N two O 5 (DINITROGEN PENTOXIDE)

Preparation :

• (common method)

• 

• 

Backdrop : Colourless crystalline solid and sublimes

It is anhydride of nitric acrid

Uses : It is powerful oxidising amanuensis

Structure :
It'south ionic structure (past X-ray) is . It is also called nitronium nitrate.

P two O 3 or P iv O six (PHOSPHORUS TRIOXIDE)

Preparation :

Properties : white solid similar wax, garlic scent, highly poisonous.

Structure :

P 2 O 5 or P 4 O ten (PHOSPHORUS PENTOXIDE) Bloom OF PHOSPHOROUS

Training :

Backdrop : White crystalline solid smells like garlic, sublimes

Uses : Powerful dehydrating amanuensis

Structure :

OXYACIDS OF Northward AND P

Both form a number of oxy acids which are as follows:

		Oxidation number	Basicity
Hyponitrous acid	H two N 2 O 2	+1
Nitroxylic acid	H 4 N two O 4	+two
Nitrous acid	HNO 2	+3
Nitric acid	HNO three	+5
Peroxynitric acrid	HNO 4	+5
Hydronitrous acid	H 2 NO 2	+2
Hypophosphorus acid	H iii PO ii	+one	1
Phosphorus acid	H 3 PO 3	+3	2
Orthophosphoric acid	H three PO 4	+5	iii
Pyrophosphoric acid	H 4 P 2 O 7	+5	4
Meta phosphoric acid	HPO 3	+5	1
Hypophosphoric acid	H 4 P ii O half dozen	+four	iv

NITROGEN

Discovered past Daniel Rutherford. Affluence in air is 78.fifteen% by volume. It occurs in combined state equally saltpetre (KNO 3 ) and Chile Saltpetre (NaNO 3 ). Information technology is also known as Azote (without life)

PREPARATION

• 

• 

• 

• . It is violent reaction with flashes of light (volcano experiment)

• 

• Preparation of very pure Northward two : Past heating Sodium azide

MANUFACTURING

LINDE'Due south OR CLAUDE'S Procedure

Atmospheric air is compressed and then released into a bigger area when liquid air is obtained (Joule Thomson event) which is mainly mixture of Northward two and O two . They are separated by fractional distillation.

PROPERTIES

• It is colourless, odourless, tasteless, slightly lighter than air, slightly soluble in water, not poisonous gas.

• It is incombustible and non supporter of combustion.

• It combines with metals and not metals to form number of compounds.

USES

To decrease concentration of oxygen in air and brand combustion less rapid. To create inert temper and in the training of NH 3 , HNO 3 , CaCN 2 , etc.

AMMONIA (NHiii)

PREPARATION

(lab method)

MANUFACTURING

• Haber's process :

Other catalysts employed are

(i) finely divided Os or U

(ii) Finely divided Ni deposited over pumice rock

(iii) Fe(OH) iii with traces of SiO 2 and K 2 O

• Cyanamide process :

Mixture of Calcium Cyanamide and graphite under the name of nitrolim is used as fertilizer.

• Serpeck'due south process : As by product during hydrolysis of AlN

Properties

• Colourless gas, characteristic pungent odor, brings tears into eyes, nerveless past downwards displacement of air.

• Extremely soluble in water due to H-bonding. It is a strong lewis base.

• Ammonia is dried over whatever metal oxide but CaO is cheaper.

• When passed through alkaline solution of Nessler'due south reagent a brown coloured complex known as Millon's base of operations is formed.

NITRIC Acid (HNO3)

as well known as aqua fortis

Training

(lab method)

MANUFACTURING

• Birkeland – Eyde process : Air is passed through an electric arc (3000ºC) when N 2 combines with O 2 to grade NO. It is cooled and allowed to combine with O 2 to course NO 2 . The latter is passed in water in presence of backlog of air to give HNO 3 .

• Ostwald's Process : From ammonia

Concrete PROPERTIES

Syrupy, colourless, pungent liquid unremarkably available as 68% and 15.7 M. Aqueous solution is often yellow due to small concentrations of NO ii

Fuming nitric acid (HNO iii + NO 2 )

Chemic Backdrop

• As an acid

It is a strong acid and in aqueous solution the ionisation is almost complete.

⇌

Thus it reacts with basic oxides, hydroxides, carbonates etc.

• Every bit oxidising agent

or (full-bodied HNO 3 )

(dil. HNO 3 )

OXIDATION OF Not METALS -IC ACIDS ARE FORMED

(Sulphuric acid)

(Carbonic acid)

(Phosphoric acid)

(Iodic acid)

(Arsenic acid)

(Metastannic acrid)

(Selenious acrid)

(Tellurous acrid)

OXIDATION OF COMPOUNDS

Action OF NITRIC ACID ON METALS

ARMSTRONG'S THEORY

The metallic first displaces nascent hydrogen from acid which farther reacts with acid to requite secondary reactions.

Factors affecting the secondary reactions

• Nature of the metal

• Concentration of the acid

• Temperature

• Presence of impurities

Activity OF NITRIC Acrid ON ZINC Under DIFFERENT Weather

• Common cold and very dil. acid evolves ammonia which reacts with HNO 3 forming ammonium nitrate

• Common cold and dil HNO 3

• Common cold and moderately conc.

• Cold and concentrated

Activity OF NITRIC Acrid ON COPPER UNDER Unlike CONDITIONS

• Cold and dil.

• Cold and moderately concentrated

• Cold and concentrated

• Hot and conc.

Metals similar Mg and Mn requite hydrogen with dil. HNO three

PASSIVITY

Metals similar, Iron, Cr, Ni, Al or Co go inactive or passive due to stable oxide layers.

Noble Metals like Pt, Pd, Bone, Ir and Au do not react with nitric acid. They react with aqua regia (1 vol. Conc. HNO three + iii vol. Conc. HCl).

Similarly platinum forms

Construction OF NITRIC Acid

USES

In the industry of fertilizers ii) For purification of silver and gold iii) In the manufacture of explosives iv) oxidising reagent v) As nitrating reagent

NITROUS Acrid (HNOtwo)

PREPARATION

• 

• 

• 

• 

Backdrop

It has slight blue color in solution may be due to anhydride North 2 O iii . It is very unstable.

• Decomposition

(automobile oxidation)

• Action of heat

• Oxidising nature

(electron acceptor)

• Reducing nature

(electron donor)

• Reaction with ammonia

• Formation of diazonium compounds

USES

In the manufacture of azo dyes.

Structure

It is a tautomeric mixture of the post-obit forms

PHOSPHOROUS

Discovered by Brand

OCCURRENCE

It occurs in combination only as phosphates

• Phosphorite Ca 3 (PO 4 ) 2

• Chlorapatite CaCl ii .3Ca 3 (PO 4 ) 2

• Fluorapatite CaF 2 .3Ca iii (PO 4 ) two

In phosphoproteins of brain, bones, teeth, milk, egg, nervous tissues of animal and plants.

MANUFACTURING

By reduction of calcium phosphate with carbon in presence of SiO two in an electric furnace

Purification : By melting under acidified solution of Thousand 2 Cr ii O 7 . The impurities are oxidised and redistilled.

PROPERTIES

Freshly prepared phosphorus is colourless. On continuing acquires pale lemon color due to formation of ruby-red phosphorus on the surface. It is therefore called yellow phosphorus. Due to its poisonous nature the jaw bones decay and disease is known equally " Phossy jaw "

ALLOTROPIC FORMS OF PHOSPHORUS AND THEIR PREPARATION

• Red phosphorous
  By carefully heating yellow phosphorus in an inert temper for well-nigh 8 days

• Violet phosphorus
  By crystallisation of white phosphorous from molten pb

• Scarlet

By exposing the solution of red P in PBr 3 to calorie-free or past humid

Past heating PBr 3 with Hg at 513K

• Blackness
  By heating white P to 473K under 1000kg/sq. cm.
  It is the most stable form, good conductor of electricity.

CHEMICAL Properties

• With non metals

  • ,

  • ,

  • 

  • 

• With metals

  • 

  • 

• With compounds

  • 

  • 

  • 

USES

In matches, explosives, every bit rat poisonous substance and in fertilizers and alloys.

Lucifer box
Side contains : Red P or P 2 S 3 + Sand + Glue

On tip : Red P + Oxidising agent like KClO 3 or KNO 3 or Pb 3 O 4 + glass pulverization or chalk for friction + glue

PHOSPHINE (PH3)

PREPARATION

• Whatsoever phosphide + H 2 O PH iii

• Decomposition of H three PO 3 :

• Lab. method :

• Pure PH 3 :

PROPERTIES

• Physical Properties : Colourless, highly poisonous, with rotten fish odor gas, slightly soluble in h2o

• Basic nature :

• Decomposition :

• Combustibility :

Pure PH iii is not spontaneously inflammable. Ordinary PH 3 is spontaneously inflammable due to the presence of P two H iv

• With metallic salts :

• With chlorine :

USES

• Holme's signals : A mixture of CaC 2 and Ca 3 P ii when treated with water, phosphine is liberated which catches burn and lights up acetylene. Called-for gases serve the purpose of a bespeak. They are used in ships.

• Fume screen : Ca 3 P 2 is used smoke screen. PH 3 obtained from information technology catches fire to requite the needed smoke.

• Celphos : It is trade name of AlP, aluminium phosphide and used equally fumigant. In presence of moisture information technology gives PH 3 which kills insects and pests

• Rat poisonous substance : Zinc phosphide Zn iii P 2 is a rat poison, which gives PH 3

ORTHOPHOSPHORIC Acid (HthreePO4)

PREPARATION

• 

• 

• 

• 

PROPERTIES

• Physical Backdrop – Colourless syrupy liquid

• Action of estrus
  

• It is tribasic and ionises in three steps

(Readily)

(Weakly)

(very weak ionisation)

• 

USES

• For training of HBr, HI in laboratory

• For preparing metaphosphoric acrid

• Stabiliser for H 2 O 2

ORTHOPHOSPHORUS Acid (H3PO3)

PREPARATION

• 

• 

Properties

• Physical Properties – Information technology crystallises as deliquescent white solid

• Acidic nature : ⇌ ⇌

• Decomposition : . This reaction is disproportionation

• Reducing nature :

(color of I 2 discharged)

USES

Every bit reducing agent

FERTILIZERS

Fertilizers are the chemical substances which are added to soil in order to make up the deficiency of nutrients required by plants. Nutrients are classified equally-

• Primary nutrients : which are consumed in big quantities eg. Nitrogen, Phosphorus and Potassium

• Secondary nutrients : Calcium and Magnesium

• Micro nutrients : which are required in infinitesimal quantities eg. Copper, Zinc, Manganese, Boron, Molybdenum, chlorine and Atomic number 26

TYPES OF FERTILIZERS

NITROGENOUS FERTILIZERS

These provide nitrogen to the plants.

• Urea

It contains about 47% Northward ii

• Ammonium sulphate (Sindri fertilizer)

• Bones Calcium nitrate
  (nitrate of lime or Norwegian saltpetre)

• Calcium cyanamide

or

PHOSPHATIC FERTILIZERS

These provide phosphorus to plants

• Super phosphate of lime

bachelor phosphorus 16 – 18% P ii O 5

• Phosphatic slag or Thomas slag

It is by product of steel industry, available phosphorus 14-18% P 2 O 5

• Triple super phosphate

• Nitrophos

POTASH FERTILIZERS

These provide potassium to plants. eg. KCl, KNO 3 , Thou ii SO iv

MIXED FERTILIZERS

• Ammoniated superphosphate
  Information technology is prepared by spraying ammoniation solution (NH 4 NO 3 = 65.0%, NH 3 = 21.vii% and H 2 O = 13.27%) on superphosphate

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Source: https://www.iitianacademy.com/p-block-elements-nitrogen-family/

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