Intro to VSEPR

In ionic bonds, electrons are ​ (a)   rather than being shared. When writing ​ a Lewis dot structure for an ionic compound, the elements' symbols are shown in a ​ (b)   with their charge and the electrons that make the ion stable. In a covalent bond, the valence electrons are ​ (c)   . When writing a Lewis dot structure for a covalent compound, the elements' symbols are written down, and the ​ (d)   electrons surround each symbol. At least one ​ (e)   of electrons are shared between the two elements.

• transferred
• bracket
• shared
• valence
• pair

How many lone pairs are present in a molecule of water?

• 1

• 2

• 3

• 4

Another way to represent a pair of electrons that surround the symbol is to draw a ​ (a)   . Each line represents a ​ (b)   . This is called a ​ (c)   . Two lines represent four electrons or a ​ (d)   .

• line
• pair of electrons
• single bond
• double bond

The ​ (a)   of a covalently bonded molecule is determined by the electron orbitals and bonds within the molecule. The ​ (b)   theory is used to predict the geometric shape of molecules. When naming the geometric shape, the bond ​ (c)   between the central atom and the adjacent atoms is significant. The bond angle is affected by the ​ (d)   pairs of electrons. Bonded pairs are those shared by the central atom and the ​ (e)   atoms in the molecule.

• shape
• VSEPR
• angle
• unbonded
• adjacent

The image here shows different ways you can depict a chemical molecule. Which of these models shows all the valence electrons?

• molecular formula

• space-filling model

• Lewis structure

• ball & stick model

In forming a molecular structure, each atom should have __ electrons around it unless there is a specific reason why this cannot be achieved.

• 2

• 4

• 6

• 8

Draw the Lewis structure for hydrogen fluoride.

Draw the Lewis structure for acetylene (C₂H₂).