Name:_______________________

Putting Ions in Their Hands Salts (Ionic Bonding)

Introduction:When working in chemistry, it is often convenient to write a chemical in symbols. For example we might write down the substance table salt as NaCl. The first time seeing formulas and names of ionic compounds can be confusing. However, upon further investigation, there are actually simplistic formulated steps to do so.

I. Using the information on Model 1, answer the following questions below:

1. Identify three elements that form only one cation.

2. Identify three elements that form only one anion.

3. Identify three elements that form more than one cation.

4. In what region of the periodic table are these “multiple positive ion” elements usually located? _______________________________

II. Using the information on Model 2, answer the following questions below:

1. Circle the symbol for the metal in each of the compounds in Model 2.

2. Which element comes first in the name and formula of the salt (metal or nonmetal)?

_____________________________ 3. In the compound zinc phosphide, what is the charge on the zinc ion and phosphide ion?

Zinc ion Phosphide ion

4. Explain why a 3 to 2 ratio of ions is necessary for the compound Zn3P2.

5. What ending is used to name the nonmetal in a binary compound?

___________6. Name the following ionic compounds (salts) using what you learned from

Model 2.

Chemical Formula

IUPAC Name

Li2OMgF2

Al2S3

K3N

7. Provide the chemical formula for each of the following ionic compounds.

IUPAC Name Chemical FormulaBarium Nitride

Magnesium Sulfide

Read This!When the metal in an ionic compound always forms an ion with the same charge, you need not indicate that charge as part of the compound name. However, some atoms have the ability to form more than one type of ion. This can make naming confusing. You can’t simply refer to a compound of copper and oxygen as “copper oxide.” People won’t know which compound you are referring to – CuO or Cu2O

III. Using the information on Model 3, answer the following questions

below:1. Model 3 is labeled “ Metals that form multiple ions.” List three other metals

that form multiple ions and could be included in Model 3.

2. Describe the most obvious difference between the names in Model 3 and those in Model 2.

_________________________________________________________________________

3. Do the Roman numerals in the name in Model 3 relate to the (a) # of cations

(b) # of anions (c) charge of the cation

(d) charge of the anion

4. Fill in the table below using what you learned from Model 3.

Compound Charge on Cation IUPAC Name of CompoundPbCl2Fe2O3

SnOCuBr2

Let’s Review:For each of the compounds in the table below, determine the type of metal in

the compound and then the name the compound using the correct naming method.

Compound (Salt)

Metal formsonly one ion

Metal formsmultiple

ions

IUPAC Name

CaBr2

MgOAg3NSnCl2CuF2

Zn3N2

HgO

Ternary Ionic Compounds

Do you know you eat a lot of “-ates”? Next time you look at a food label, read the ingredients and you will likely find a number of ingredients that end with “-ate,” such as sodium phosphate or calcium carbonate. Did you ever wonder what the chemical formulas of these ingredients look like? In this section you will explore polyatomic ions, which are group of atoms that carry a charge. These ions are found in our food ingredients, natural waterways, and many other chemical compounds you encounter every day.IUPAC Name Ion Symbols and Charges Chemical FormulaBarium nitriteAluminum carbonateAmmonium phosphateIron III hydroxideAluminum sulfiteCopper II nitrate

Writing formulas for ionic compounds may be simply determined by following the steps below:

1. The cation is always written first; the anion is written second.2. The overall’s charge for an ionic compound is always zero. The charges of the

individual ions are never included in the compound’s formula.3. Subscripts are used to indicate the number of atoms of each element in the

compound.4. Parentheses are used around polyatomic ions to show that the subscript pertains

to the polyatomic ion as a whole.5. Assumed subscripts of one are omitted when writing chemical formulas.

Procedure:1. Obtain a bag of ions from your teacher and separate the cations from the anions.2. Locate the data table and the Ion Formula Chart.3. From the cation and anion cards, locate ion cards for the first two combining ions

listed in the first column of the data table. The first two, for example, are the aluminum cation and chloride anion. Copy the ionic formula for each ion into the

first column of the data table. Use the Ion Formula Chart to look up the ion formulas.

4. Put the cards for the two combining substances together on a flat surface adding additional cards of the same ion until the heights of the cation and anion column are equal. For example, every aluminum cation needs three chloride anions (see Figure 1).

5. Count the number of each ion necessary for the heights to be equal (i.e., for the compound to form). For example, one aluminum cation combines with three chloride anions. Record the number of each ion used in Columns 2 and 3 of the data table. Notice that the numbers recorded in Columns 2 and 3 are the subscripts in the chemical formula of the compound.

6. Determine the total positive charge of the cation card(s) and the total negative charge of the anion card(s) used in forming the compound. These two values will be equal yet opposite in value. For example, the total positive charge is +3 (from one aluminum with a +3 charge) and the total negative charge is –3 (from three chlorides, each with a –1 charge). Record the ionic charges in Columns 4 and 5 of the data table.

7. Write the formula for the ionic compound, using subscripts to indicate the number of each kind of ion used (from Columns 2 and 3). Follow the rules for writing ionic formulas listed in the background material. In our example, the formula is AlCl3. Record the chemical formula for the ionic compound in Column 6 of the data table.

8. Write the name of the ionic compound following the rules for naming ionic compounds described in the table below. Record the name for the ionic compound in the last column of the data table.

9. After writing formulas for all 16 sets of combining ions listed in the data table, complete rows 17-20 of the data table by randomly choosing four more sets of combining ions (that have not already been combined). Follow the procedure of steps 3-8 to complete each column of the data table.