Acids https://youtu.be/5Qc_Sy6IAlI
All acids will end in the word “acid”. (ex. Hydrochloric acid) For right now a compound is an acid if it STARTS WITH a H Not always true in real life, but it will be for us at this moment in time. All acids will end in the word “acid”. (ex. Hydrochloric acid)
When to include prefix “Hydro” You use the “Hydro” prefix only when the formula includes hydrogen and one other element. (not polyatomic) HCl = hydrochloric acid Short Formula = Long Name Always “Hydro(Insert element here)-ic Acid
When Not to Include “Hydro” If there is a polyatomic Ion present NO HYDRO HClO3 = chloric acid Long Formula = Short Name
One last thing…. When naming acids with polyatomics, sometimes there are two ions with similar names: Ex) Nitrate and Nitrite If the polyatomic ion ends in “–ate”, then the suffix “-ic” will be added. Example – Nitrate HNO3 Nitric Acid If the polyatomic ion ends in “–ite”, then the suffix “-ous” will be added. Example – Nitrite HNO2 Nitrous Acid
Examples: H2S Polyatomic Ion? the formula is “short”, so the name is long , hydro is needed. What is the ending? Hydrosulfuric acid
H2SO4 Polyatomic ion? The formula is long, so the name is short No need for “hydro” What is the ending? Name: Sulfuric acid
HNO2 Polyatomic ion? The formula is long, so the name is short no need for “hydro” What is the correct ending? Name: Nitrous acid
Writing Formula Help SOXS! Find oxidation numbers (charges) and criss cross as you would with ionic compounds. If name is long (includes Hydro) then it is the element hydrogen and another element from periodic table. If the name is short, you have a polyatomic ion. Look for “ –ic” or “-ous” to determine which polyatomic ion to use.
Phosphoric acid Name short- formula long (polyatomic) use oxidation numbers to get the formula H3PO4 Hydrophosphoric acid long name- short formula – criss cross ox # H3P Phosphorous acid Short name Long formula (Polyatomic) H3PO3
Practice! HF H2CrO4 HClO2
Practice Writing! Hydrosulfuric Acid Acetic Acid Phosphoric Acid