Writing Formulas Assignment
~ Practice writing formulas for compounds given the name of the compound
~ See how common these compounds are in our everyday lives
~ Find ingredient labels (NOT “Nutrition Facts”) of different items
~ Find names of compounds that you know how to write the formula for
~ Cut out, copy, scan, or cut and paste the label you found the name(s) on
~ Tape, glue, or staple the label onto a regular-sized piece of paper (8 ˝” x 11”)
~ Underline or highlight the name of the compound on the label, if possible.
~ Write the formula for the compound next to the label.
~ Only write the formula for a compound one time each on this assignment – even if you find
the compound on several different labels.
~ You can use as few or as many labels as you need to get your required number of
~ You MUST have the label or a copy of each label included when you hand in the assignment.
~ Please number your compounds so it is easier for me to grade.
~ Honors level classes – total of 15 DIFFERENT compounds
~ Standard level classes – total of 10 DIFFERENT compounds
Chicken, Chicken By-Product Meal, Corn Meal, Brewers Rice, Chicken Fat (preserved with mixed Tocopherols, a source of Vitamin E), Ground Whole Grain Sorghum, Dried Beet Pulp, Fish Meal, Chicken Flavor, Dried Egg Product, Fish Oil (preserved with mixed Tocopherols, a source of Vitamin E), Brewers Dried Yeast, Potassium Chloride, Salt, Fructooligosaccharides, Monosodium Phosphate, Choline Chloride, Minerals (Ferrous Sulfate, Zinc Oxide, Manganese Sulfate, Copper Sulfate, Manganous Oxide, Potassium Iodide, Cobalt Carbonate), Vitamin E Supplement, DL-Methionine, Calcium Carbonate, Vitamins (Ascorbic Acid, Vitamin A Acetate, Calcium Pantothenate, Biotin, Thiamine Mononitrate (source of vitamin B1), Vitamin B12 Supplement, Niacin, Riboflavin Supplement (source of vitamin B2), Inositol, Pyridoxine Hydrochloride (source of vitamin B6), Vitamin D3 Supplement, Folic Acid), Rosemary Extract.
~ “Monosodium Phosphate” should be just sodium phosphate (No Greek prefixes when there
is a metal in the compound!) Na+1 PO4-3 Formula = Na3PO4
NOTE: Be sure not to repeat this compound even if you see it listed as “disodium phosphate”,
“trisodium phosphate”, or “sodium phosphate”
~ Notice that I did not highlight “Choline Chloride”, “Thiamine Mononitrate”, or “Pyrodoxine Hydrochloride” in green.
THAT’S BECAUSE WE DIDN’T LEARN HOW TO WRITE THE FORMULAS FOR THOSE COMPOUNDS!
This assignment is not meant for you to look up the formulas on the internet – it is meant for you to practice what
you learned in class!
~ There are many acceptable compounds on this label. I have highlighted these compounds in green.
Not all are addressed in these directions.
~ Some labels may incorrectly use transition metals in compounds. For example, the label
above says "Copper Sulfate". That is incorrect because it does not tell the oxidation number of
copper. Use the Periodic Table given in class to find the most common oxidation number of
the transition metal and use that.
~ Be sure to read the entire name of the compound - from one comma to the next. There will be
ingredients listed like "sodium aluminum phosphate" or "calcium disodium EDTA". Neither
of these is acceptable for this assignment.
~ There are some polyatomic ions that we haven't learned or used, but will be acceptable to
use. These polyatomic ions include: silicate, molybdate, selenate, and selenite.*
~ For whatever reason, it seems that pet food, nutritional drinks, and vitamins have many
acceptable compounds in them. You may want to look to these types of items to start.
~ This assignment is due at the beginning of the class period on THURSDAY, 3/29/12.
These polyatomic ions follow the same pattern as other elements in the same
For example, “silicate” implies that silicon is in the polyatomic ion. Well, silicon is
in the same group as carbon, and therefore it behaves like carbon. We know that
there is a polyatomic ion called carbonate, and it has the formula CO3-2. It would
stand to reason that silicate would be SiO3-2. Follow this example if you decide to use
molybdate, selenate, or selenite.