Understanding Selenium and Lewis Structures

This video tutorial explains how to draw Lewis structures for selenium (Se) and its ion Se2-. It begins by identifying the number of valence electrons for selenium using the periodic table, noting that selenium has six valence electrons. The tutorial then demonstrates how to draw the Lewis structure for neutral selenium by placing these electrons around the Se atom. For the Se2- ion, the video explains that the ion has two extra electrons, resulting in a total of eight valence electrons, which are added to the Lewis structure. The video concludes by highlighting the stability of the Se2- ion and the importance of using brackets to indicate its ionic nature.

What is the main focus of this video tutorial?

• Explaining the periodic table layout.

• Discussing chemical reactions of selenium.

• Understanding the history of selenium.

• Drawing Lewis structures for selenium and its ion.

How many valence electrons does selenium have?

• 4

• 6

• 8

• 2

Which group in the periodic table does selenium belong to?

• Group 14

• Group 12

• Group 16

• Group 18

What is the Lewis structure for neutral selenium?

• Selenium with 4 valence electrons.

• Selenium with 2 valence electrons.

• Selenium with 6 valence electrons.

• Selenium with 8 valence electrons.

What does the 2- charge indicate for the Se2- ion?

• It has lost two electrons.

• It has lost two protons.

• It has gained two protons.

• It has gained two electrons.

How many valence electrons are present in the Se2- ion?

• 6

• 2

• 8

• 4

Why is the Se2- ion considered stable?

• It has a full outer shell of 4 electrons.

• It has a full outer shell of 8 electrons.

• It has a full outer shell of 2 electrons.

• It has a full outer shell of 6 electrons.

What should be added around the Se2- ion in its Lewis structure?

• Parentheses

• Brackets

• Curly braces

• Quotation marks

What is the purpose of drawing Lewis structures?

• To predict the color of elements.

• To calculate the density of elements.

• To understand the electron arrangement in molecules.

• To determine the atomic mass of elements.

What is the final step in drawing the Lewis structure for an ion?

• Adding extra protons.

• Adding extra neutrons.

• Adding extra electrons.

• Adding extra atoms.