COVALENT BONDS 1
Learning Targets 1 and 2 Pre Assess Big Ideas Post Assess I can define, identify, and diagram covalent bonds I can determine the number of bonds formed by atoms when forming molecules. 2
WHAT IS A COVALENT BOND? H H N N A covalent bond is when atoms share electrons. O O 3
What type of elements form covalent bonds? Covalent bonds often occur between nonmetals. The reason that atoms are able to bond is that the attractions are strong enough in both directions (protons for electrons) from both atoms. There must also be room for electrons in the outer energy level of both atoms. In a covalent bond, both atoms attract the two shared electrons a the same time. t 4
What groups will form covalent bonds? 5
HOW DO COVALENT BONDS FORM? Let's take a closer look on how covalent bonds form by viewing this tutorial... TEACHERS DOMAIN COVALENT BONDING TUTORIAL 6
Learning Target I can predict the formula for simple covalent molecules. Learning Targets 3 and 4 Pre Assess Big Ideas Post Assess I can correctly name covalent compounds. 7
Bell work (Write the questions). 1. What is a covalent bond? 2. What elements are involved in forming covalent bonds? 3. When two nonmetal atoms are close together, how does the movement of electrons change? 4. What does the graph tell us about the potential energy of hydrogen atoms when they form a covalent bond? 8
Lewis Dot Lewis Dot Diagrams help to determine how many pairs of electrons can be shared. For example, how many pairs of electrons can be shared in Fluorine gas? Nitrogen gas? F one unpaired electron = single bond N three unpaired electron = triple bond 9
H H 10
Single Bonds IN A SINGLE BOND, ATOMS SHARE A PAIR OF ELECTRONS. H 2 = Hydrogen Gas SHARES 2 ELECTRONS SHARES 2 ELECTRONS H H Forms a single bond 11
Practice Illustrate the covalent bonds between the following atoms: Two Chlorine Atoms INCLUDE: One Hydrogen and One Chlorine STRUCTURAL FORMULA LEWIS DOT STRUCTURE SHOWING THE SHARING OF ELECTRONS FORMULA NAME OF THE COMPOUND 12
Cl Cl H Cl Cl Cl H Cl 13
ANSWERS WERE YOU RIGHT? H HCl Cl Cl Cl 2 Cl H Cl Cl Cl Hydrogen Chloride CHLORINE GAS 14
O O 15
DOUBLE BONDS In a double bond, atoms share 2 pairs of electrons. O o 2= Oxygen Gas O O O SHARES FOUR ELECTRONS O O SHARES FOUR ELECTRONS 16
PRACTICE ILLUSTRATE THE COVALENT BONDS BETWEEN THE FOLLOWING: INCLUDE: ONE CARBON AND TWO OXYGEN ATOMS ONE OXYGEN AND TWO HYDROGEN ATOMS STRUCTURAL FORMULA LEWIS DOT STRUCTURE SHOWING THE SHARING OF ELECTRONS FORMULA NAME OF THE COMPOUND 17
ANSWERS WERE YOU RIGHT?? H 2 O H O H O CO 2 C O H O H O C O WATER CARBON DIOXIDE 18
COVALENT BONDS N 2 = Nitrogen Gas N N N N N Forms a triple bond N 19
TRIPLE BONDS In a triple bond, atoms will share 3 pairs of electrons N 2 = Nitrogen Gas SHARES 6 ELECTRONS N N SHARES 6 ELECTRONS 20
When are atoms the most stable? THE ATOMS IN A COVALENT BOND ARE MORE STABLE WHEN THEY ARE BONDED TOGETHER THAN WHEN THEY ARE APART THE LOWER THE ENERGY = THE MORE STABLE THE BOND 21
Learning Target I can predict the formula for simple covalent molecules. Learning Targets 3 and 4 Pre Assess Big Ideas Post Assess I can correctly name covalent compounds. 22
Bell Work Take 2 minutes to think about ionic bonds and covalent bonds and how they form. Write down all of the similarities and differences that you can between the two in your composition books. Now, "Give one and Get one" with 3 people at a different table and return to your seat. 23
Learning Target 5 Learning Target Pre Assess Big Ideas Post Assess I can distinguish between ionic and covalent compounds. 24
NAMING COMPOUNDS COVALENT COMPOUNDS ARE NAMED USING PREFIXES TO INDICATE THE NUMBER OF EACH TYPE OF ATOM PRESENT IN THE MOLECULE Mono = 1 Di = 2 Tri = 3 Tetra = 4 Penta =5 Hexa = 6 CO 2 = Carbon Dioxide Cl 2 O = Dichlorine Monoxide SO 3 = Sulfur Trioxide 25
Rules for Naming Binary Covalent Compounds Rule 1. The element with the lower group number is written first in the name; the element with the higher group number is written second in the name. Exception: when the compound contains oxygen and a halogen, the name of the halogen is the first word in the name. 26
Rules for Naming Binary Covalent Compounds Rule 2. If both elements are in the same group, the element with the higher period number is written first in the name. Rule 3. The second element in the name is named as if it were an anion, i.e., by adding the suffix ide to the name of the element. Rule 4. Greek prefixes (see the Table provided at the bottom of this page) are used to indicate the number of atoms of each nonmetal element in the chemical formula for the compound. Exception: if the compound contains one atom of the element that is written first in the name, the prefix "mono " is not used. 27
Naming Binary Covalent Compounds Rule 4. Greek prefixes (see the Table provided at the bottom of this page) are used to indicate the number of atoms of each nonmetal element in the chemical formula for the compound. Exception: if the compound contains one atom of the element that is written first in the name, the prefix "mono " is not used. prefix mono 1 di 2 tri 3 tetra 4 penta 5 hexa 6 hepta 7 octa 8 nona 9 deca 10 number indicated 28
CAN YOU NAME THE FOLLOWING? CO 2 S 2 O 3 NO 2 CCl 4 SO N 2 O 3 Carbon Dioxide Disulfur Trioxide Nitrogen Dioxide Carbon Tetrachloride Sulfur Monoxide Dinitrogen Trioxide 29
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Attachments covalent bonds teacher domain.zip