Before you work on this prelesson you have to understand ions. Please complete all the Ionic Notation study helps and come back here afterward.

1. Ionic compounds are compounds that consist of:

   1.   ?    two non-metals.
   2.   ?    two metals.
   3.   ?    a metal and a non-metal.

2. We call them ionic compounds because they are made up of ions. Which of the following are ions?
   
   (Click here if you don't know what an "ion" is.)

   1. Ca
   2. Na
   3. Mg
   4. H¹⁺
   5. O^2-
   6. Na¹⁺
   7. Be²⁺
   8. Cl^1-
   Check

3. Positive ions will attract

   1.   ?    negative ions
   2.   ?    nothing
   3.   ?    neutral atoms
   4.   ?    positive ions

4. Negative ions will attract

   1.   ?    nothing
   2.   ?    negative ions
   3.   ?    neutral atoms
   4.   ?    positive ions

5. Neutral atoms will attract

   1.   ?    positive ions
   2.   ?    negative ions
   3.   ?    neutral atoms
   4.   ?    nothing

6. Ionic compounds combine together so that they are neutral and will not attract any more ions. If it is neutral what must be true?

   1.   ?    There must be more neutral charges than positive or negatives.
   2.   ?    The positive charges must be greater than the negative charges.
   3.   ?    The negative and positive charges must be equal.
   4.   ?    The negative charges must be greater than the positive charges.

7. Each ionic compound has a formula (like H₂O). An ionic compounds formula tells you the smallest number of each element that can make an equal amount of positive and negative charge.
   
   Which of these has an equal amount of positive and negative charge?

   1.   ?    K¹⁺O^2-
   2.   ?    Be²⁺Cl^1-
   3.   ?    Ca²⁺F^1-
   4.   ?    Na¹⁺Cl^1-

8. Table salt's ionic formula is NaCl because Na has a 1+ charge and Cl has a 1- charge. And 1 -1 = 0, a neutral compound.
   
   Which of the following is a neutral compound?
   

   1.   ?    Na¹⁺O^2-
   2.   ?    K¹⁺N^3-
   3.   ?    Mg²⁺Cl^1-
   4.   ?    Be²⁺S^2-

9. Which of the following are balanced, neutral compounds?

   1. Be²⁺S^2-
   2. K¹⁺Ne⁰
   3. Na¹⁺Cl^1-
   4. Mg²⁺F^1-
   5. H¹⁺N^3-
   6. Al³⁺N^3-
   7. Li¹⁺O^2-
   Check

10. What are the positive and negative numbers next to the chemical sybols (like the 2+ in Ca²⁺)?

    1.   ?    oxidation numbers
    2.   ?    number of protons
    3.   ?    valence electrons
    4.   ?    number of electrons

11. If two ions do not have the same charge, then it will have a net charge and attract other ions of opposite charge.
    For instance: Na¹⁺ and O^2-.
    
    What would be the net charge on this compound?

    1.   ?    1-
    2.   ?    1+
    3.   ?    2-
    4.   ?    0

12. Na¹⁺ and O^2-
    Net charge = -1.
    
    If it is negative, what will it attract?
    

    1.   ?    a positive ion
    2.   ?     a neutral ion
    3.   ?    a negative ion
    4.   ?    nothing

13. Na¹⁺ and O^2-
    Net charge = -1.
    It will attact another Na¹⁺.
    
    If each Na has a 1+ charge, how much total charge would two Na's have?

    1.   ?    +3
    2.   ?    +2
    3.   ?    0
    4.   ?    +1

14. Na¹⁺Na¹⁺ and O^2-
    
    What is the total charge of this compound now?

    1.   ?    -1
    2.   ?    +2
    3.   ?    +1
    4.   ?    0

15. Na¹⁺Na¹⁺ and O^2-
    
    Na and O will combine with 2 sodiums (Na) and 1 oxygen, giving a net charge of zero (+2 - 2 = 0).
    
    Last, write the formula as a chemist would. What is the ionic compound formula for combining Na and Cl?

    1.   ?    Na₂O
    2.   ?    not enough information given
    3.   ?    NaO₂
    4.   ?    NaO

16. Na₂O is a balanced ionic compound. Na and O will combine with two sodiums (Na) and only one oxygen.
    
    If it is balanced what is its charge?

    1.   ?    2+
    2.   ?    1-
    3.   ?    0
    4.   ?    1+

17. Which of the following are balanced ionic compounds?

    1. H¹⁺H¹⁺P^3-
    2. Mg²⁺Mg²⁺N^3-
    3. Al³⁺Cl^1-Cl^1-Cl^1-
    4. K¹⁺K¹⁺O^2-
    5. Na¹⁺S^2-
    6. Li¹⁺Li¹⁺S^2-
    Check