Experiment 6: Nomenclature |
Page 40: Objectives
1. Learn the seven diatomic elements.
2. Learn names and correct charges of monatomic ions.
3. Write names and formulas of binary compounds.
These objectives seem a bit boring but learning the language of chemistry is like learning any language. It gives you the ability to talk to people you couldn't talk to before. If you haven't already, look at my tutorials on nomenclature. Here's the menu page:
http://www.chemistryland.com/CHM130W/06-Nomenclature/NomenclatureMenu.htm
Learning nomenclature can be like learning words to another language, but it doesn't help if you learn the word and don't know what it is. For example, you can learn how to pronounce and write the French word, "la pomme". That is fine, but you also need to know what it means (It means apple by the way). The same is true in chemistry nomenclature. This lab has a lot of chemical names that you will learn to write. But this is just part of learning about chemicals. You should also what they look like and what they might be used for. That's when Wikipedia or Google is useful. Just do a search in Wikipedia and you often get a picture plus some background information on that chemical compound.
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Binary compounds: Write names and formulas for compounds.
Tip on finding formula: Atoms that have a charge have a one-track mind. They are attracted to anything with the opposite charge. In the table below the positive metal ions on the left column will all be attracted to the negative non-metal ions on the top row. If the positive metal ion is 1+ and the negative ion is 1-, after they combine, their charges balance out to zero. Being zero charge, they will not attract any other atoms. So the final formula is set as one each. For example, Na+ + Cl- --> NaCl. Also, Ag+ + Cl- --> AgCl. If the metal ion is 2+ and the non-metal ion is 2-, they will also cancel their charges when they combine. So the final formula is one each. For example, Fe2+ + O2- --> FeO. Now lets look at Na+ being attracted to O2-. After they combine, there's still a negative one charge because (+1) + (-2) = (-1). So NaO still has a negative one charge (NaO-). That means they will attract another positive sodium ion (Na+). So, NaO- + Na+ --> Na2O. At this point the charges all cancel and Na2O is neutral so there's no more attraction, meaning that's the final formula. Remember, atoms can't think, but they can still make the right formula by simply coming together as long as there's a charge present.
Tip on finding name: When there are just two kinds of atoms, the name of the compound begins with the name of the positive ion (usually a metal). The second word is the name of the negative element except the name is shortened and "ide" is added. Most of these are done. You can do the blank ones on your own.
| |
Cl- |
O2- |
N3- |
S2- |
P3- |
Na+ |
NaCl
Sodium chloride |
Na2O
Sodium oxide |
Na3N
Sodium nitride |
Na2S
Sodium sulfide |
Na3P
Sodium phosphide |
Mg2+ |
MgCl2
Magnesium chloride |
MgO
Magnesium oxide |
Mg3N2
Magnesium nitride |
MgS
Magnesium sulfide |
Mg3P2
Magnesium phosphide |
Al3+ |
AlCl3
Aluminum chloride |
Al3O2
Aluminum oxide |
AlN
Aluminum nitride |
Al2S3
Aluminum sulfide |
AlP
Aluminum phosphide |
Fe2+ |
FeCl2
Iron(II) chloride |
FeO
Iron(II) oxide |
Fe3N2
Iron(II) nitride |
FeS
Iron(II) sulfide |
Fe3P2
Iron(II) phosphide |
Ag+ |
AgCl
Silver chloride |
Ag2O
Silver oxide |
Ag3N
Silver nitride |
|
|
Cu+ |
CuCl
Copper(I) chloride |
|
|
|
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Notice some metals have a Roman numeral after them and some don't. If the metal can only have one charge, then there's no reason to indicate the charge. Some metals, however, can have different charges so we have to indicate their charge. If they aren't in Group 1 or 2, you have to look up which are which.
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Names and formulas of compounds
Fill in the missing information
Name |
Formula
(Note: I added an equation to show how the ions combined) |
| Potassium sulfide |
(K+ + K+ + S2- --> K2S) |
| Silver bromide |
(Ag+ + Br- --> AgBr) |
| Dinitrogen tetroxide |
N2O4 |
| Nickel(II) sulfide |
(Ni2+ + S2- --> NiS) |
| Magnesium phosphide |
(Mg2+ + Mg2+ + Mg2+ + P3- + P3- --> ???) |
| Calcium oxide |
(Ca2+ + O2- --> ???) |
| Chlorine trifluoride |
ClF3 |
| Normally chlorine is seen at the end (Like NaCl). The more positive atom is written first. When non-metals combine with metals, the metals have the positive charge and is written first. In this case chlorine is more positive than fluorine, so chlorine is written first. |
| Lithium nitride |
??? |
| Copper(I) phosphide |
Cu3P |
| Since the phosphorus ion is a 3- charge and we see 3 copper atoms, that means the the copper must have a plus one charge. 3x(1+) balances with 3-. |
| Aluminum chloride |
??? |
| Sodium hydride |
NaH |
| Iron(III) iodide |
??? |
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Page 45: Objectives
1. Distinguish between binary and ternary compounds.
2. Learn names and correct charges of polyatomic ions.
3. Write names and formulas of compounds. |
Complete the tables by writing names and formulas of compounds as appropriate (Some are done and others are left for you to do).
Ternary Compounds
| |
CN- |
NO3- |
CO32- |
SO42- |
PO43- |
NH4+ |
NH4CN
Ammonium cyanide |
NH4NO3
Ammonium nitrate |
(NH4)2CO3
Ammonium carbonate |
|
(NH4)3PO4
Ammonium phosphate |
Ca2+ |
Mg(CN)2
Magnesium cyanide |
Mg(NO3)2
Magnesium nitrate |
|
|
|
Al3+ |
Al(CN)3
Aluminum cyanide |
|
Al2(CO3)3
Aluminum carbonate |
Al2(SO4)3
Aluminum sulfate |
|
Cu2+ |
Cu(CN)2
Copper(II) cyanide |
Cu(NO3)2
Copper(II) nitrate |
CuCO3
Copper(II) carbonate |
|
Cu3(PO4)2
Copper(II) phosphate |
| Notice that iron (III) below has the same charge as aluminum above so the number of the anions (negative ions) will be the same. Since iron has more than one oxidation number, we must indicate which one it is. When aluminum combines, it only has a +3 charge, so there's no reason to indicate the charge. |
Fe3+ |
Fe(CN)3
Iron(III) cyanide |
Fe(NO3)3
Iron (III) nitrate |
Fe2(CO3)3
Iron(III) carbonate |
Fe2(SO4)3
Iron(III) sulfate |
|
| To find names, you can learn the rules. Also, if you have Internet access, try typing the formula in the search field (like in Google). For example, to find the name of H2CO3 type H2CO3 in the search field. You will likely see websites that show the name of carbonic acid. |
H+ |
HCN
hydrogen cyanide if gas
hydrocyanic acid if in water |
|
H2CO3
Carbonic acid |
Sulfuric acid
|
H3PO4
Phosphoric acid |
|
Name |
Formula (Note: I added an equation to show how the ions combined) |
| Potassium sulfate |
(K+ + K+ + SO42- --> K2SO4) |
| Ammonium bromite |
(NH4+ + BrO2- -->???) |
| Zinc nitrate |
[Zn2+ + NO3- + NO3- --> ???] |
| Sodium sulfite |
(Ni2+ + SO32- --> ???) |
| Iron(II) carbonate |
(Fe2+ + CO32- -->???) |
| Magnesium hydrogen phosphate |
(Mg2+ + HPO42- --> ???)
Note: Phosphate (PO43-) has negative 3 charge, but when combined with H+, one of the negative charges is canceled. So the result is a negative 2 charge. Since Magnesium ion is plus 2, the charges combine to be zero with one each. |
| Calcium chlorate |
(Ca2+ + ClO3- + ClO3- --> ???) |
| Cobalt(III) acetate |
[ Co3+ + C2H3O2- + C2H3O2- + C2H3O2- -->???] |
| Sodium chromate |
( Na+ + CrO4- --> ???) |
| Potassium dichromate |
??? |
| Aluminum nitrate |
??? |
| Mercury (II) cyanide |
??? |
| Manganese hydroxide |
??? |
| Lithium hypochlorite |
??? |
Sodium hydrogen carbonate
(sodium bicarbonate) |
??? |
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Page 48: Experiment 6
Names and formulas of ionic compounds and their parent acids
By "parent acid" it means that you can start with this acid and the "offspring/product" is the salt in the left column. For example, starting with phosphoric acid, one can add sodium hydroxide (NaOH), and it will form sodium phosphate (Na3PO4). Here's the reaction in water (aq):
2H3PO4(aq) + 6NaOH(aq) ==> 2Na3PO4(aq) + 3H2O(l)
The acid (H+) and the base (OH-) make water. If solution is dried, you get sodium phosphate powder.
Here is reaction for copper (II) sulfate:
Cu(OH)2(aq) + H2SO4(aq) ==> CuSO4(aq) + 2H2O(l)
The solution is blue and if dried, then you get blue copper(II) sulfate powder.
Compound |
Color of Compounds |
Ion giving color |
Anion Formula |
Parent Acid |
Formula |
Name |
Formula |
Name |
| Na3PO4 |
sodium phosphate |
White |
both ions are colorless |
PO43- |
H3PO4(aq) |
phosphoric acid |
| NaCl |
sodium iodide |
White |
both ions are colorless |
Cl- |
HCl(aq) |
hydrochloric acid |
| KI |
??? |
White |
both ions are colorless |
I- |
HI(aq) |
hydroiodic acid |
| K2CrO4 |
potassium chromate |
Yellow |
CrO42- |
CrO42- |
H2CrO4(aq) |
chromic acid |
| CuSO4 |
copper (II) sulfate
Since sulfate is 2-, Cu must be 2+. Copper has varied charge so we show (II) |
Blue |
Cu2+ |
SO42- |
H2SO4(aq) |
sulfuric acid |
| CaCO3 |
??? (chalk) |
White |
both ions are colorless |
CO32- |
H2CO3(aq) |
carbonic acid |
| MgSO4 |
???? (Epsom salts) |
White |
both ions are colorless |
SO42- |
H2SO4(aq) |
sulfuric acid |
| CoCl2 |
Cobalt (?) chloride
(hint: Cl is 1-, so Cl2 is 2-, so what is charge of cobalt?) |
Blue |
Co2+ |
Cl- |
HCl(aq) |
hydrochloric acid |
| FeSO4 |
Iron (?) sulfate |
Blue/Green |
Fe2+ |
SO42- |
H2SO4(aq) |
sulfuric acid |
| NiCl3 |
Nickel (?) chloride |
Green |
Ni3+ |
Cl- |
HCl(aq) |
hydrochloric acid |
| Cr2(SO4)3 |
Chromium (?) sulfate
(3 sulfates have a total charge of 6-, so two chromiums must have 6+. So what is the charge of just one chromium?) |
|
Cr3+ |
SO42- |
H2SO4(aq) |
sulfuric acid |
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(Page 49) Questions:
Name or write the correct formula for each compound whichever is appropriate. Check the ion chart to be sure that you have the correct formula and charge for each ion. Then check the formula for the compound to see that the total positive charge = total negative charge.
Name (Note: I added equation to show how ions came together) |
Formula |
| Potassium sulfate (K+ + K+ + SO42- ==>???) |
|
| Ammonium nitrate (NH4+ + NO3- ==>???) |
|
| Nickel (II) sulfide (Ni2+ + S2- ==>???) |
|
| Chromium (III) chloride (Cr3+ + Cl- ==>???) |
|
| Dinitrogen tetroxide (No ionic bonds. These are two non-metals which have covalent bonds. N2 + 2O2 ==>???) |
|
| Hydroiodic acid |
|
| Iron (II) chlorate [Fe2+ + ClO3- + ClO3- ==> ???] |
|
| Chlorine trioxide (Note: This looks like chlorate (ClO3- )but there is no negative sign, and there's no metal in front. So this is a covalent binary compound.) |
|
| Potassium manganate |
|
| Sodium dichromate |
|
| Mercury (?) sulfide (Note: mercury can have more than one charge so we need to indicate it with Roman numeral. What is the charge of sulfide? That will determine what mercury's charge is.) |
|
| |
FePO4 |
| These are two non-metals. So we just say the name and indicate the number plus the second one has "ide" ending. So it's "silicon dioxide". |
SiO2 |
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Complete the table below:
Compound Formula |
Anion Formula
(negative ion) |
Parent Acid |
Formula |
Name |
| PbCl2 |
|
(see earlier table) |
| Al(NO3)3 |
|
HNO3(aq) |
Nitric acid |
| Na2SO4 |
(see earlier table) |
(see earlier table) |
|