Understanding Ions and Their Charges

The video tutorial explains how to determine the number of electrons lost or gained in ions. It uses examples of oxygen (O2-) and sodium (Na+) ions to illustrate the process. For O2-, the video shows that it gains two electrons, resulting in a total of ten electrons. For Na+, it loses one electron, resulting in ten electrons. The tutorial emphasizes understanding the atomic number and how it relates to electron count in neutral atoms.

What is the primary focus when discussing ions?

• Nuclear reactions

• Protons and neutrons

• Atomic mass

• Gaining or losing electrons

What does a negative charge on an ion indicate?

• The ion has gained protons

• The ion has lost protons

• The ion has gained electrons

• The ion has lost electrons

How many electrons does a neutral oxygen atom have?

• 6

• 8

• 10

• 12

How many electrons does an O2- ion have in total?

• 8

• 14

• 10

• 12

What is the charge of an ion that has gained two electrons?

• 1+

• 2+

• 1-

• 2-

What happens to an atom when it becomes a cation?

• It gains electrons

• It loses electrons

• It loses protons

• It gains protons

What is the atomic number of sodium (Na)?

• 11

• 12

• 13

• 10

How many electrons does a neutral sodium atom have?

• 11

• 10

• 12

• 9

How many electrons does Na+ have after losing one electron?

• 11

• 10

• 12

• 9

Which of the following ions has lost an electron?

• F-

• O2-

• Na+

• Cl-