Before you work on this prelesson you have to understand ions. Please complete all the Ionic Notation study helps and come back here afterward.
Ionic compounds are compounds that consist of:
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.)
Positive ions will attract
Negative ions will attract
Neutral atoms will attract
Ionic compounds combine together so that they are neutral and will not attract any more ions. If it is neutral what must be true?
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?
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?
Which of the following are balanced, neutral compounds?
What are the positive and negative numbers next to the chemical sybols (like the 2+ in Ca2+)?
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 O2-.
What would be the net charge on this compound?
Na1+ and O2-
Net charge = -1.
If it is negative, what will it attract?
Na1+ and O2-
Net charge = -1.
It will attact another Na1+.
If each Na has a 1+ charge, how much total charge would two Na's have?
Na1+Na1+ and O2-
What is the total charge of this compound now?
Na1+Na1+ and O2-
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?
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?
Which of the following are balanced ionic compounds?