Classifying Inorganic Compounds (Section 8.1 pg 201-208)

So far, we’ve been generally looking at inorganic compounds– compounds that don’t contain a high % of carbon by weight. There are 2 main types of inorganic compounds (Fig.2 p.202):

Inorganic molecular compounds are molecules formed with 2 non-metals (but no C or very little C!). Common examples: water (H2O), ammonia (NH3), CO2 (counts as low % of C).

Inorganic ionic compounds are divided into three categories: Acids, Bases and Salts. Acids = any substance that releases H+ ions in solution (they usually start with an H-) Bases = any substance that releases OH- ions in solution. (They usually end in -OH) Salts = any ionic substance that does not have an H+ or OH- ion.

Chemical indicators are commonly used in labs to test for acids/bases (Table 2 p.203 & Data Pages

Please note H2O is basically composed of one H+ ion and one OH- ion (Fig.4 p.204). Please read the section ‘Acidity’ on p.204 of your text – good info.

Acidity is a measure of the relative amounts of H+ and OH- ions in solution (Table 4 p.205) – the higher the number of H+ ions in solution the more acidic it is (opposite is true for basic solutions). Check out the pH scale in your Data Pages – gives examples of the pH of common solutions.

The pH scale is used to measure acidity (see Fig. 6&8 p. 205-6) The pH scale is used to measure acidity (see Fig.6&8 p.205-6). On this scale acids have a pH 0-7, pH = 7 is neutral, and pH 7-14 is basic. The pH scale is logarithmic, meaning that every 1 point on the scale represents 10 times more or less acidity (see Table 5 p.206).

There are a separate set of rules for naming acids – please see the flow chart handout (Fig.9 p.207).

Naming Acids HBr H2SO4 HNO2 HF H2S H3PO4

Naming Acids HBr Hydrobromic acid H2SO4 Sulfuric acid HNO2 Nitrous acid HF Hydrofloric acid H2S Hydrosulfuric acid H3PO4 Phosphoric acid

To name a base or a salt we follow the rules used for naming ionic compounds (Table 7 p.208). NaOH Magnesium hydroxide Ammonium hydroxide Ca(OH)2 NH3 NaOH Sodium hydroxide Mg(OH)2 Magnesium hydroxide NH4OH Ammonium hydroxide Ca(OH)2 Calcium hydroxide NH3 Ammonia

Questions Pg. 209 # 4 + worksheet