Exploring Atomic and Ionic Radius Trends

This video tutorial covers the concepts of atomic and ionic radii, explaining how atomic radius varies across the periodic table and the factors affecting it, such as effective nuclear charge and electron distance. It also discusses ionic radius changes when atoms become anions or cations, highlighting the role of electron-electron repulsion and nuclear charge. The video includes comparisons of isoelectronic species and provides practice questions to reinforce understanding.

Which factor primarily determines the atomic radius when comparing elements across a period?

• Number of electron shells

• Number of neutrons

• Effective nuclear charge

• Atomic mass

Why does barium have a larger atomic radius than magnesium?

• Barium has fewer protons

• Barium has more occupied energy levels

• Magnesium has a higher effective nuclear charge

• Magnesium is a metal

What is the main reason for the smaller atomic radius of fluorine compared to lithium?

• Lithium has a higher atomic mass

• Lithium has more protons

• Fluorine has a greater effective nuclear charge

• Fluorine has fewer electron shells

Why is the atomic radius of iodine larger than that of chlorine?

• Chlorine has fewer electron shells

• Chlorine has a higher effective nuclear charge

• Iodine has more occupied energy levels

• Iodine has more protons

What happens to the size of an atom when it gains an electron to become an anion?

• It becomes larger

• It remains the same

• It depends on the element

• It becomes smaller

Why is a cation always smaller than the atom from which it is derived?

• It has more protons

• It has fewer electron shells

• It has more electrons

• It has a higher atomic mass

What does it mean for two species to be isoelectronic?

• They have the same number of protons

• They have the same number of neutrons

• They have the same electron configuration

• They have the same atomic mass

Which of the following species is NOT isoelectronic with Krypton?

• Sr2+

• Br-

• K+

• Rb+

Arrange the following ions in order from smallest to largest: F+, F, F-, F2-.

• F2-, F-, F, F+

• F, F+, F-, F2-

• F-, F2-, F, F+

• F+, F, F-, F2-

Which ion is the smallest among the following: Ca2+, K+, Cl-, S2-?

• Ca2+

• K+

• Cl-

• S2-