Understanding Ionic Radii

The video tutorial explains the concept of ionic radii, highlighting that ionic radii follow similar trends to atomic radii, increasing down a group and decreasing across a period. It compares the sizes of various ions, such as lithium, sodium, and potassium, and explains why negatively charged ions are larger than positively charged ones. The tutorial also covers specific examples, comparing ions like beryllium vs magnesium, calcium vs gallium, and sodium vs its ion. It concludes with a discussion on isoelectronic ions and their size ranking.

What happens to the size of ions as you move down a group in the periodic table?

• They get smaller.

• They get larger.

• They remain the same.

• They fluctuate randomly.

What is the general trend for ionic radii as you move across a period?

• Ionic radii fluctuate randomly.

• Ionic radii remain constant.

• Ionic radii decrease.

• Ionic radii increase.

Why is the magnesium ion larger than the beryllium ion?

• Beryllium has a higher nuclear charge.

• Magnesium has more electron shells.

• Magnesium is higher on the periodic table.

• Magnesium has fewer electrons.

Which ion is smaller, calcium or gallium, and why?

• Calcium, because it has a lower charge.

• Gallium, because it is to the right of calcium on the periodic table.

• Calcium, because it is above gallium on the periodic table.

• Gallium, because it has fewer protons.

When comparing potassium and bromide ions, which is larger and why?

• Bromide, because it has fewer electrons.

• Potassium, because it has more protons.

• Bromide, because it has more electron shells.

• Potassium, because it is a cation.

How does the size of a sodium ion compare to its parent atom?

• The sodium ion is smaller.

• They are the same size.

• The sodium ion has more electrons.

• The sodium ion is larger.

What is the effect of adding an electron to a chlorine atom to form a chloride ion?

• The chloride ion loses an electron shell.

• The chloride ion becomes larger.

• The chloride ion remains the same size.

• The chloride ion becomes smaller.

Which of the following ions is the largest: oxide, fluoride, sodium, or magnesium?

• Magnesium

• Sodium

• Fluoride

• Oxide

What does it mean for ions to be isoelectronic?

• They have the same ionic charge.

• They have the same atomic number.

• They have the same number of protons.

• They have the same number of electrons.

Which ion is larger, sodium or magnesium, and why?

• Sodium, because it has a lower positive charge.

• Magnesium, because it has fewer electron shells.

• Magnesium, because it has more protons.

• Sodium, because it is higher on the periodic table.