Presentation on theme: " What is an ionic bond? What is a covalent bond? Draw a picture of an ionic bond for salt (NaCl) DO NOW."— Presentation transcript:
What is an ionic bond? What is a covalent bond? Draw a picture of an ionic bond for salt (NaCl) DO NOW
CHEMICAL BONDING AND COMPOUND NAMING
Ionic compounds form crystals What do you notice about the pictures? IONIC COMPOUNDS
Strong attractions between ions of a compound cause it to have High melting points Highly brittle (breakable) Very strong Cation anion IONIC COMPOUNDS
How do we form an ion? SPEAKING OF IONS
Ions- an atom with either a positive (cation) or a negative (anion) charge caused by the addition or removal of an electron. Why do we add or remove electrons? IONS
ELECTRONS are the reason we have compounds! All bonding is caused by either the transfer or sharing of electrons! When electrons are shared it is _________ bonding. When electrons are transferred it is _________ bonding. BONDING
Do you like being unstable? Think about standing on the side of a cliff….with a very strong wind. Would you be happy? How do elements gain stability? ALL ELEMENTS WANT TO BE STABLE
What is a valence electron? What is the octet rule? THE OCTET RULE
Compounds are most stable when they have eight (8) valence electrons. Compounds will gain or give up electrons based on how easy it is. Ionization energy- the amount of energy required to remove an electron. THE OCTET RULE
In your notebook explain how ionization energy changes across the periodic table. You have 3 minutes. Use full sentences!!!!!!! (I’m serious…I will be checking!) OCTET RULE
CARE TO SHARE?
What ionic charge will Magnesium have? When is an atom least likely to react? Define ion, ionization energy, valence electron, octet rule, covalent bond, and ionic bond. *Bonus* how many protons, neutrons, and electrons does Bromine have? HOMEWORK 12/2/13
You need to pick up a white board, dry erase marker, and eraser from the front left corner of the room. You must be seated with these materials by the time the bell rings or points will be deducted from your grade today. DO NOW
Draw a water molecule. Chemical formula H 2 O. Is water a compound, mixture, or element? How many elements are in a molecule of water? What’s an ionic bond, covalent bond? DO NOW CONTINUED
LETS BREAK IT DOWN Many water molecules together Pure substance not a mixture
The word molecule is ambiguous. What does ambiguous mean??? You can have a molecule of an element You can have a molecule of a compound You can have a molecule of a substance The word molecule does NOT always mean compound or element. THE WORD MOLECULE
Tricky right? There are elemental forms of all elements. Air is made mostly of what element? HOW CAN TWO ATOMS TOGETHER BE AN ELEMENT?
Just Remember! STABILITY rules the UNIVERSE! All chemical bonding is done to make an element stable. CONFUSED?
What is a covalent bond? You can make one covalent bond for every valence electron you have. COVALENT BONDING
Covalent bonds are expressed as lines. Unlike ionic expressed as charges. COH COVALENT BOND
The types of atoms in a molecule and its shape affect its polarity. What do you see when you look in a mirror? NON-POLAR COVALENT
For non-polar elements you look for equality in the molecule. NON-POLAR COVALENT
To be polar you should look for unequal sharing. The unequal sharing will cause some charges on molecules BUT due to the fact there is no electron transfer it is still a covalent bond. POLAR COVALENT
What is the strongest type of bond? Polar molecules will attract to one another through intermolecular forces. Which makes polar substances stronger than non-polar. POLARITY AND STRENGTH Intermolecular forces
Ionic > polar covalent > non-polar BOND STRENGTH
Draw these molecules in your notebook and label them as either polar or non-polar molecules. PRACTICE
1. What is ionic bond? 2. What is a covalent bond? 3. Draw a picture of an ionic bond for salt (NaCl). Today’s Lesson Topic: Chemical Naming DO NOW
DO NOW ANSWER
SWBAT name common mono-atomic and polyatomic ions. Essential Questions: how do chemical compounds get their name? TODAY’S OBJECTIVE
Ionic Bond vs. Covalent Bond Ionic bond is an electron transfer Covalent Bond is electron sharing Which is stronger? Why? REVIEW..
How many elements are in the following compound? Na 2 CO 3 LET’S CHECK…
There are so many ways to combine atoms. We must give compounds names. To do this there are rules….many many rules Fortunately this is not organic chemistry (you’ll get that in college) Fewer rules to follow for physical science (yay!) But, you will need to memorize some rules. NAMING COMPOUNDS
HOLD UP…REVIEW What is a Cation? What is an Anion? A cation is an ion with a positive charge An ion an with a negative charge
REVIEW What are the ions of Na, C, N, O, Cl ?
In ionic bonding we join an anion with a cation. The first step to naming is to determine which is which. IONIC COMPOUND NAMING
1. In NaCl which would be the anion? 2. In CaCl 2 which would be the anion? 3. In LiS which would be the anion? Sensing a pattern? IDENTIFYING THE ANION
In ionic bonding the anion is usually listed second in the chemical formula. IONIC COMPOUND NAMING
THE ONLY RULE YOU NEED FOR ANION NAMING! CHANGE THE ENDING OF THE CHIMICAL NAME TO –ide. Example: Fluorine = Fluoride ion (F-) ANION RULE
PRACTICE 1: NAME THESE 1. Cl N Br O -2
PRACTICE 2: WRITE THESE 1. Sulfide ion 2. iodide ion 3. phosphide ion 4. Fluorine ion
This rule is easy. Use the element name of the cation. NaCl = sodium chloride Sodium is the cation Chloride is the anion CATION RULE
1. NaCl 2. CaCl 2 3. MgO 2 PRACTICE 3: NAME THESE
To complicate things we have polyatomic ions. What are they? Multiple atoms in an ion. Multiple atoms with a charge Example: NH 4 + ammonium Unfortunately, these are ion names you must memorize. THAT NAMING SYSTEM WORKS FOR MONO-ATOMIC IONS
COPY THESE IN YOUR NOTES PUT YOUR PENCIL DOWN WHEN DOWN AND WAIT SILENTLY
Any trends you see? Elements ending in –ate? TRENDS?
MOLECULAR COMPOUNDS Molecular compounds are named based on the number of atoms in a molecule.
WHAT IS THE COMMON NAME FOR CO2? What about CO3? Carbon Trioxide
PRACTICE 4: MOLECULAR COMPOUNDS In order to name you just add the prefix to the elemental name (with –ide). 1. CO 2. PO 5
YOU TRY 3. PO 3 4. SO 4 (careful with this one) 5. N 2 O 4
FINAL REVIEW Name the following compounds: 1. NaCl 2. NaO 3. H2O 4. LiF
1. What are anions? What are cations? 2. What is the name of CaCl2? 3. What is the name of NaCl? 4. What is the name of EXIT TICKET