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Saturday, August 7, 2021
Why is AlCl3 in covalent and AlF3 in ionic?
Tuesday, February 16, 2021
NCl3 and PCl3 on hydrolysis give different kinds of products. These is because of
(A) Attack of lone pair of water takes place to N and P respectively.
(B) Attack of lone pair of water takes place to Cl and Cl respectively.
(C) Attack of lone pair of water takes place to Cl and P respectively.
(D) None of these
Solution: (C) Their is no vacant d- orbitals hence attack of lone pair of water takes place to Cl and P respectively.
Related Questions:
Question(1): Why aqueous solution of AlCl3 is acidic in nature ?
Question(2): What happen when aq AlCl3 react with Acid or Base?
Question(3): Although anhydrous aluminium chloride is
covalent but its aqueous solution is ionic in nature. Why?
Question(4): Arrange in increasing order of extent of hydrolysis [ CCI4, MgCI2,
AICI3, PCl5, SiCI4].
Question(5): Although Sulphur contain vacant d-orbital but SF6 does not undergo
hydrolysis. Why ?
Question(6): CCl4 can not be hydrolysed but SiCl4 can be. Why?
Question(7): What
are the hydrolysis products of urea ?
Question(8): Why
SF6 is inert where as SF4 is highly reactive towards H20
?.
Question(9): Why
SF6 behave inert towards hydrolysis?
Question(10): Why PCl3 hydrolysed while NCl3 can not be hydrolysed?
Question(11): Why hydrolysis of NCl3 gives NH4OH and HOCl, while PCl3 on hydrolysis gives H3PO3 and HCl?
Why hydrolysis of NCl3 gives NH4OH and HOCl, while PCl3 on hydrolysis gives H3PO3 and HCl?
The hydrolysis of PCl3 may be contrasted with that of NCl3 this difference is due to the change in polarity of P-Cl bond in PCl3 in contrast to N-Cl bond in NCl3.
PF3 is not sensetive to H2O
due to strong P-F bond F being more electronegative than oxygen forms a strong covalent bond with
p in coparison with P-O bond.
Related Questions:
Question(1): Why aqueous solution of AlCl3 is acidic in nature ?
Question(2): What happen when aq AlCl3 react with Acid or Base?
Question(3): Although anhydrous aluminium chloride is
covalent but its aqueous solution is ionic in nature. Why?
Question(4): Arrange in increasing order of extent of hydrolysis [ CCI4, MgCI2,
AICI3, PCl5, SiCI4].
Question(5): Although Sulphur contain vacant d-orbital but SF6 does not undergo
hydrolysis. Why ?
Question(6): CCl4 can not be hydrolysed but SiCl4 can be. Why?
Question(7): What
are the hydrolysis products of urea ?
Question(8): Why
SF6 is inert where as SF4 is highly reactive towards H20
?.
Question(9): Why
SF6 behave inert towards hydrolysis?
Question(10): Why PCl3 hydrolysed while NCl3 can not be hydrolysed?
Thursday, January 28, 2021
Hydrolysis reactions (Inorganic reactions):
Hydrolysis is a chemical process in which a certain molecule is split into two parts by the addition of a molecule of water. One fragment of the parent molecule gains a hydrogen ion (H+) from the addition of water. The other group collects the remaining hydroxyl group(OH-) for examples :
(1) During hydrolysis of a covalent compound having non
metal central atom, if water molecule attack at central atom and hydrolysis
occurs at room temperature then oxy acid of the non metal will be formed, if
the central atom is in it one of the common oxidation state. Oxidation state of central atom of the oxy acid will be same as its in the given substrate,
However this rule is not applicable to XeF2, XeF4 and XeF3.
(2) hydrolysis reactions occur in non redox
reaction except XeF2 and XeF4 and mixed anhydride i.e. central atoms has its
uncommon oxidation state for examples;
(3) During hydrolysis, hybridization of central atom in
transition state and may or may not change.
(4) BF3, SiF4, CCl4,
SbCl3, and BiCl3 undergo partial hydrolysis even in
excess of water while PCl5, SF4, SeF6,IF7,
XeF6 H4P2O8, H2S2O8,P4O10
can undergo partial as well as complete hydrolysis by adjusting the amount
water.
(5) Rate of hydrolysis is directly proportional
to the positive (+) charge density at least electronegative atoms of substrate provided. And the least electronegative atom must contain vacant orbital and have no crowding.The order of rate of hydrolysis of some compounds are given
as;
PCl5(V) > SiCl4(IV) > AlCl3(III)
> MgCl2(II) > CCl4 (NO vacant orbital) > SF6
(Crowding)
Related Questions:
Question (1): Why aqueous
solution of AlCl3 is acidic in nature?
Question (2): What happen when
aq AlCl3 react with Acid or Base?
Question (3): Although
anhydrous aluminium chloride is covalent but its aqueous solution is ionic in
nature. Why?
Question (4): Arrange in
increasing order of extent of hydrolysis [ CCI4, MgCI2,
AICI3, PCl5, SiCI4].
Question (5): Although Sulphur
contain vacant d-orbital but SF6 does not undergo hydrolysis. Why?
Question (6): CCl4 can
not be hydrolysed but SiCl4 can be. Why?
Question (7): What are the
hydrolysis products of urea?
Question (8): Why SF6 is
inert where as SF4 is highly reactive towards H20?.
Question (9): Why SF6 behaves
inert towards hydrolysis?
Question (10): Why PCl3 hydrolysed
while NCl3 can not be hydrolysed?
Question (11): Why hydrolysis
of NCl3 gives NH4OH and HOCl, while PCl3 on hydrolysis gives H3PO3 and HCl?
Question (12) NCl3 and PCl3 on
hydrolysis give different kinds of products. These is because of
Saturday, January 2, 2021
Why aqueous solution of AlCl3 is acidic in nature ?
Aluminium forms covalent compound with chloride because lionization enthalpy (∆iH= +5137 kJ/mole) of Aluminium is very high due to small size and chlorine is unable to convert Al into Al+3 ions.
However, when anhydrous AlCl3 (which is covalent in character) is dissolved in water, it undergoes hydration as follow:
AI2CI6 + H2O -->2[Al(H2O)6]+3 +(∆H)
Hydration of
anhydrous Aluminium chloride is highly exothermic in nature. The hydration
enthalpy is more than ionisation enthalpy of aluminium.This hydration enthalpy
removes all the three valence electrons of the aluminium leading to the
formation of Al3+ more easly.This AI3+ is
hydrated with water and form a complex ion. Thus in water Al exist as [Al(H2O)6]+3. so aqueous AlCl3 form Hexahydrated complex salt.
Related Questions:
(1) Although anhydrous aluminium chloride is covalent but its aqueous solution is ionic in nature. Why?
(2) Why Ga has small size than Al exceptionally
(3) Why aqueous solution of borax reacts with two moles of acids ?
(4) What is structure of solid Ortho Boric acid ?
(5) What is the structure of trimetaboric acid and trimetaborate ion?
(6) Why Borazine is more reactive than benzene towards Electrophic Aromatic substitution reactions ?
(7) Why Borazine (B3N3H6) is also known as inorganic benzene ?.
(8) Why B-F bond length in BF3 is shorter (130 pm) than B-F bond Iength in BF4- (143 pm)?. Explain.
(9) Why B-F do not exist as dimer?. Explain.
(10) Although anhydrous aluminium chloride is covalent but its aqueous solution is ionic in nature. Why?
(11) Why Boric acid become strong acid in the presence of cis 1,2-diol or 1,3-diol ?
(12) Four-center two-electron bond (4C-2e Bond): Structure of AlCl3:
(13) What is the molecular formula of Borax ?
(14) What is the difference between the structure of AlCl3 and diborane?
Sunday, December 27, 2020
What happen when aq AlCl3 react with Acid or Base?
When a soluble aluminium salt is placed in water at room temperature. Initially the aluminium ion is surrounded by six water molecules and the complex ion has the predicted octahedral Geometry.
This complex ion behaves as an acid in water, losing protons, and a series of equilibria are established (H+ is used, rather than H3O+for simplicity):These equilibria give rise to an acidic solution in water, to the Hexahydroxoaluminate(iii) ion [Al(OH)6]3- in a strongly alkaline solution, and only in strongly acidic solutions is the hexaaquo ion [Al(H2O)6]3+ found.
The solid
hydrate, often written AlCl3. 6H2O and more correctly [Al(H2O)6]Cl3 can, therefore,
only be obtained from a strongly acidic solution. The reaction with water
resulting in the liberation of a proton is again known as hydrolysis and occurs whenever the
central metal ion is small and highly charged (i.e. having a high surface
density of charge), for example in salts of iron(III), chrornium(III).
Related
Questions:
(1) Although anhydrous aluminium chloride is covalent but its aqueous solution is ionic in nature. Why?
(2) Why Ga has small size than Al exceptionally
(3) Why aqueous solution of borax reacts with two moles of acids ?
(4) What is structure of solid Ortho Boric acid ?
(5) What is the structure of trimetaboric acid and trimetaborate ion?
(6) Why Borazine is more reactive than benzene towards Electrophic Aromatic substitution reactions ?
(7) Why Borazine (B3N3H6) is also known as inorganic benzene ?.
(8) Why B-F bond length in BF3 is shorter (130 pm) than B-F bond Iength in BF4- (143 pm)?. Explain.
(9) Why B-F do not exist as dimer?. Explain.
(10) Although anhydrous aluminium chloride is covalent but its aqueous solution is ionic in nature. Why?
(11) Why Boric acid become strong acid in the presence of cis 1,2-diol or 1,3-diol ?
(12) Four-center two-electron bond (4C-2e Bond): Structure of AlCl3:
(13) What is the molecular formula of Borax ?
(14) What is the difference between the structure of AlCl3 and diborane?
Why SF6 is inert while SF4 is a very reactive molecule that reacts with H2O rapidly and vigorously?
The fact that SF6
does not react with water is not due to thermodynamic stability. Rather, it is
because there is no low-energy pathway for the reaction to take place (kinetic stability).
Six fluorine atoms surrounding the sulfur atom
effectively prevent attack of water molecules and the sulfur atom has no
unshared pairs of electrons where other molecules might attack. In SF4
, not only is there sufficient space for an attacking species (water) to gain
access to the sulfur atom, but also the unshared pair is a reactive site. As a
result of these structural differences, SF6 is relatively inert,
whereas SF4 is very reactive.
Related Questions:
Thursday, November 12, 2020
What is hydrolysis products of "Marshall's acid ?
What is hydrolysis products of "Caro's" acid ?
Saturday, November 7, 2020
Why halogens are insoluble in water ?
Related Questions:
Monday, October 5, 2020
Why does SiCl4 undergo hydrolysis whereas CCl4 doesn't?
Tuesday, February 11, 2020
Why SF6 behave inert towards hydrolysis?
Related Questions:
Sunday, February 9, 2020
Why SF6 is inert where as SF4 is highly reactive towards H20 ?.
Related Questions:
Question (1): Why aqueous solution of AlCl3 is acidic in nature?
Question (2): What happen when aq AlCl3 react with Acid or Base?
Question (3): Although anhydrous aluminium chloride is covalent but its aqueous solution is ionic in nature. Why?
Question (4): Arrange in increasing order of extent of hydrolysis [ CCI4, MgCI2, AICI3, PCl5, SiCI4].
Question (5): Although Sulphur contain vacant d-orbital but SF6 does not undergo hydrolysis. Why?
Question (6): CCl4 can not be hydrolysed but SiCl4 can be. Why?
Question (7): What are the hydrolysis products of urea?
Question (8): Why SF6 is inert where as SF4 is highly reactive towards H20?.
Question (9): Why SF6 behaves inert towards hydrolysis?
Question (10): Why PCl3 hydrolysed while NCl3 can not be hydrolysed?
Question (11): Why hydrolysis of NCl3 gives NH4OH and HOCl, while PCl3 on hydrolysis gives H3PO3 and HCl?