Covalent Bonds 7.1.6

Covalent Bonds
Lesson 7.1.6

Draw

What are your favorite things to put on you sloppy joe?

Notebook
Page 138

Gluco - from Greek for sweet

Ose - added to end of names of sugars

Glucose - a sugar created by plants during photosynthesis

Glucose

​Co - from Latin meaning come together

Valent - meaning outer level of electrons

Bond - hold together

Covalant Bond - chemical bond where atoms share electrons to hold them together

​​Covalent Bonds

Multiple Choice

Let's Check from yesterday's Lesson

What are valence electrons?

• the electrons on the inner energy level of an atom

• the electrons that are on the outer most energy level

• all the electrons in an atom of an element

Multiple Choice

What is the magic number atoms want to be stable or "happy" in their outer shell?

• 5

• 6

• 7

• 8

​Let's figure out how many atoms of each element are in the following formulas!

​Fe₂O₃

​Na₂CO₃

​Cu(NO₃)₂

​C =
H =
O =

Remember Groups on the Periodic Table have same Valence Electrons

Glucose is a common molecule found in organisms.

C₆H₁₂O₆ - formula for glucose

We use glucose for energy!

Glucose is held together by covalent bonds.

Let's Explore Covalent Bonds!

​

​Glucose

Covalent bonds occur between 2 nonmetals or a metalloid and nonmetal

​Pink = metals
Blue = Nonmetals
Green - Metalloids

​Atoms form covalent bonds to gain a stable outer shell.
Remember the octet rule!

Multiple Choice

Which pair of atoms is most likely to form a covalent bond?

• sodium and chlorine

• hydrogen and potassium

• nitrogen and chlorine

They are STRONG attractive forces that form when atoms share electrons with each other.

They form to meet the octet rule.

​

​Covalent Bonds

Lewis structure uses dots to represent the valence electrons of an atom. (small molecules)

A structural formula uses lines to represent covalent bonds. (large molecules)

Remember, no model is ever 100% accurate.

​Modeling Covalent Bonds

Lewis Structure Examples

How many electrons does each element need to reach the octet rule?
Choose one and place your answer and element name in the chat!

Draw each element with the valence electrons represented.

First

​Identify the pair of electrons the atoms will share.

​​Second

​Continue Pairing until the Octet rule has been satisfied.

​​Third

​Draw the full molecule.

​​Fourth

​Steps to Drawing Lewis Structures

​​First look at the Lewis structure to see how many hydrogen and sulfur atoms were needed to bond.

​​Check the periodic table to see which is farther to the LEFT. That element will get listed first!

​​Now combine the information to get Hydrogen Sulfide
or
H₂S

​What if we wanted to give the chemical formula for this molecule?

Multiple Choice

How many electrons does one atom of phosphorus have?

• 15

• 30

• 31

• 3

Multiple Choice

How many neutrons does one atom of phosphorus have?

• 15

• 30

• 31

• 16

Multiple Choice

How many energy levels does an atom of phosphorus have?

• 3

• 4

• 5

• 6

Multiple Choice

How many valence electrons does an atom of phosphorus have?

• 4

• 5

• 6

• 7

Multiple Choice

What does phosphorus need to create covalent bonds and be stable?

• gain or share 5 electrons

• lose or give away 5 electrons

• gain or share 3 electrons

• lose or give away 3 electrons

Draw

Draw the Lewis dot structure for Nitrogen and Hydrogen's covalent bond.

Nitrogen has 5 valence electrons and Hydrogen has 1 valence electron.

FUN FACT - This forms ammonia.

Multiple Choice

How many electrons does an atom need in its outer shell to be stable?

• 5

• 7

• 9

• 8

Multiple Choice

How many atoms of Phosphorus are in the formula PH₃ ?

• 1

• 3

• 0

• 4

Multiple Choice

How many atoms of Carbon are in glucose C₆H₁₂O₆ ?

• 6

• 12

• 18

• 24

Draw

Draw the Lewis structure to show how phosphorus and fluorine form covalent bonds to make a molecule.

Hint: fluorine has 7 valence electrons & phosphorus has 5!

See you Tomorrow!
Remember our LAB on COVALENT BONDS is on Friday!

​

​Have a great day!

Exploring Covalent Bonds

​

​Watch the Video on Page 3 of Edio

Watch video on page 4
to see how covalent bonds are important to Earth!

Multiple Choice

Which term and picture do not go together?

• atom

• valence electrons

• molecule