Chemistry-
General
Easy
Question
The property of hydrides of p–block elements mostly depends on :
i) electronegativity difference between central atom and hydrogen
ii) size of central atom
iii) number of valence electrons in central atom Some undergo hydrolysis in which central atom is less electronegative, react with OH– to give hydrogen While acidic property of hydride in a period depends on electronegativity of central atoms, iemore electronegative is the n a group, acidic property is proportional to size of central atom Some electronIatom, more acidic is hydride deficient hydride behaves as Lewis acid while only one hydride of an element in p–block behaves as Lewis base with lone pair of electrons Hydrides in which central atom’s electronegativity is close to hydrogen has no reaction with water
Which one is the weakest acid among the following ? I</span
- HF
- HCl
- HBr
- H
The correct answer is: HF
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The small size and high charge of Al3+ ion gives it a high charge density which is responsible for its tendency to show (a) covalency in its compounds in the gaseous state (b) high hydration energy which stabilizes its compounds in Solution, and (c) high lattice energy of its compounds in the Sol. id state Thus aluminium can forms both covalent and ionic bond Like halides of boron, halides of aluminium do not show back bonding because of increase in size of aluminium Actually aluminium atoms complete their octets by forming dimers Thus chloride and bromide of aluminium exist as dimers, both in the vapour state and in polar-Sol. vents like benzene while the corresponding boron halides exists as monomer In boron trihalides the extent of back bonding decreases with increase in size of halogens and thus lewis acid character increases All BX3 are hydroly sed by water but BF3 shows a different behavior.
Which one of the following statements is correct ?
The small size and high charge of Al3+ ion gives it a high charge density which is responsible for its tendency to show (a) covalency in its compounds in the gaseous state (b) high hydration energy which stabilizes its compounds in Solution, and (c) high lattice energy of its compounds in the Sol. id state Thus aluminium can forms both covalent and ionic bond Like halides of boron, halides of aluminium do not show back bonding because of increase in size of aluminium Actually aluminium atoms complete their octets by forming dimers Thus chloride and bromide of aluminium exist as dimers, both in the vapour state and in polar-Sol. vents like benzene while the corresponding boron halides exists as monomer In boron trihalides the extent of back bonding decreases with increase in size of halogens and thus lewis acid character increases All BX3 are hydroly sed by water but BF3 shows a different behavior.
Which one of the following statements is correct ?
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