Lewis Structures and Valence Electrons

The video tutorial explains how to draw the Lewis Structure for the cyanide ion (CN-). It begins by counting the valence electrons using the periodic table, identifying carbon and nitrogen's groups, and accounting for the negative charge. The tutorial then demonstrates placing electrons between carbon and nitrogen to form bonds, ensuring both atoms achieve a complete octet. The structure is finalized with a triple bond, and the ion is represented with brackets and a negative sign. The video concludes by noting that CN- is a linear molecule.

What is the first step in drawing a Lewis Structure for an ion like CN-?

• Count the valence electrons

• Draw single bonds between atoms

• Determine the shape of the molecule

• Identify the central atom

How many valence electrons does Carbon have?

• Six

• Four

• Two

• Eight

What is the total number of valence electrons in the CN- ion?

• Eleven

• Eight

• Nine

• Ten

What is the next step after placing two electrons between Carbon and Nitrogen?

• Add more electrons to Carbon

• Complete the octet for Nitrogen

• Remove electrons from Nitrogen

• Add a double bond

How many bonds are formed between Carbon and Nitrogen in the final Lewis Structure of CN-?

• One

• Two

• Three

• Four

Why is it necessary to add brackets and a negative sign to the Lewis Structure of CN-?

• To represent the shape of the molecule

• To show the molecule is an ion

• To indicate the molecule is neutral

• To highlight the central atom

What is the shape of the CN- molecule?

• Linear

• Tetrahedral

• Trigonal planar

• Bent