Below is a one-stop shop for the key points you'll need to know for Monday's test. (It's all just a repeat of the review.)
Extra credit will be given for extra practice, so be on the look out for embedded links (bold and italicized)!
Happy studying!

Elements, Valence Electrons, and IONs, oh my!

Elements-

• ​Identify as metal or non-metal
• Find an atom's number of electrons.
• Find an atom's number of valence electrons

​Ions- 

• Know what cations and anions are.
• From the name alone, you should be able to figure out an ion's charge

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Types of Bonds

1. Ionic
2. Covalent
3. Metallic

Bonding is an interaction between two (or more) atoms. Being present in the outermost shell, valence electrons are the particles involved in this process. They can be gained, lost, or shared. We focused on the 2 types below.

Ionic Bonds- electrons gained/lost

• ​Metal + Non-metal
• Cation + Anion
• Metal loses electron to the non-metal. This is done to make both more stable. (Octet rule!)
• bond occurs when the resulting (oppositely charged) ions attract each other. 

Covalent Bonds- electrons                                        shared

• 2 non-metals share the electrons they have to become stable​
• No gaining or losing of electrons, so there are no charges (no ions!)

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Can you calculate...?

How ​many TOTAL electrons will the ION version of an element have?

The total number of electrons an atom starts off with equals the number of protons = the atomic number.
Once electrons are gained or lost, this number will change in the same way. For example...
                                         O2+ is oxygen with a 2+ charge (2 electrons were lost)
                                                 Oxygen's atomic number is 8, so it had 8 electrons originally.
                                                 Total number of electrons = 8 - 2 = 6 electrons are left. 
 If the ion is negative, you gained electrons, so you'll add the number you gained to your original total.

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NAMING AND WRITING COMPOUNDS ​

The test will cover 2-element (or binary) compounds. 
In order to answer these questions you'll need to use a combo of the knowledge above. How-to steps below:

Writing Formulas from a name:

1. Find and write down the elements' symbols
2. Identify the elements as metal or non-metal.
3. Metal + non-metal = Ionic; 2 non-metals = covalent
4. For Ionic bonds- Find the charges for each & 'drop and swap'. 
5. For Covalent bonds- The prefixes will tell you what subscript to put on each element. 

Naming Compounds:

1. Identify the elements and write down their names.
2. Determine if Ionic or Covalent (See #2 & 3 above)
3. If Ionic- Do NOT use prefixes 
4. If Covalent- Use prefixes to indicate how much you have of each element. Do NOT use 'mono-' on the first element.
5. In both cases, show the two elements are a compound by ending the name in '-ide'

Transition Metals (a special case):

• ​​The charges on these metals are always positive and are indicated by a Roman numeral in their name. 
• Only seen in ionic compounds, so no prefixes, but you DO need to include the correct Roman numeral every time.

Kahoot!

More practice? See Kahoot! above.
More help? See the tutorial below.

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