Ionic Radii:
The ionic radius of an ion is the radius of the ion when considered spherical. Cations have smaller radii than
the
corresponding atoms, while anions have larger radii. The size of ions changes based on the effective nuclear
charge and electron-electron repulsion.
Covalent Radii:
Covalent radius is half the single bond length between two similar atoms
covalently bonded in a
molecule. It helps determine the size of atoms in a molecule and plays a crucial role in bond formation and
molecular shapes. Ionic and covalent radii are essential in understanding the properties and behavior of
chemical
compounds.
What is the definition of ionic radius?
The ionic radius of an ion is the radius of the ion considered to be spherical in shape.
How does the ionic radius of a cation compare to the atomic radius of the element it is derived from?
The ionic radius of a cation is smaller than the atomic radius of the element it is derived from.
Explain the trend in ionic radius for anions compared to the atomic radius of the corresponding atom.
The ionic radius of an anion is greater than the atomic radius of the corresponding atom.
What happens to the ionic radius of Na when it forms a Na+ ion?
The radius of Na atom reduces from 186 pm to 95 pm after conversion into Na+ ion.
How does the ionic radius of Cl- change when it forms a Cl- ion?
The ionic radius of Cl- ion increases from 99 pm to 181 pm.
How does the ionic radius of a cation compare to the atomic radius of the element it is derived from?
a) Cationic radius is larger
b) Cationic radius is smaller
c) Cationic radius remains the same
d) Cationic radius varies depending on the element
Answer: b) Cationic radius is smaller
What happens to the ionic radius of an anion compared to the atomic radius of the corresponding atom?
a) Anionic radius decreases
b) Anionic radius increases
c) Anionic radius remains constant
d) Anionic radius is unrelated to the atomic radius
Answer: b) Anionic radius increases
Which factor contributes to the decrease in cationic radius for divalent and trivalent ions?
a) Increase in electron-electron repulsion
b) Decrease in effective nuclear charge
c) Increase in the valence shell electrons
d) Greater force attracting remaining electrons due to successive loss of electrons
Answer: d) Greater force attracting remaining electrons due to successive loss of electrons
How is the ionic radius of an ion related to the interionic distance in a crystal lattice?
a) It is half the interionic distance
b) It is equal to the interionic distance
c) It is double the interionic distance
d) It is triple the interionic distance
Answer: b) It is equal to the interionic distance
What is the ionic radius of an ion defined as?
a) Radius of the ion in a molecule
b) Radius of the ion in a crystal lattice
c) Radius of the ion considering it to be spherical
d) Radius of the ion in a covalent bond
Answer: c) Radius of the ion considering it to be spherical