8.1 Classifying Inorganic Compounds
Acidity
Acidity is described, then, as a measure of the relative amounts of H and OH in a solution. It follows that the higher the relative number of H ions, the higher the acidity. - Acidic: H⁺>OH⁻ ex. HCl (aq) provides extra H⁺ - Neutral:H⁺=OH⁻ ex. H₂O, NaCl (aq) - Basic: H⁺<OH⁻ ex. NaOH (aq) provides extra OH⁻
Metal Oxides
Metal Oxides dissolve in water to make BASIC solutions and is a chemical compounds that contains a metal chemically combined with oxygen. Eq.Na₂O(aq) + H₂O → 2NaOH(aq) This is a base, which is also known as sodium hydroxide
Non-Metal Oxides
Non-Metal Oxides dissolve in water to make an ACIDIC SOLUTION and its a chemical compound that contains a non-metal chemically combined with Oxygen. An example is carbon dioxide which combines with water to form an acid.This acid can react chemically with a base to form a salt.
How to name Acids that end in -IDE
Step 1: Examine the Formula and see if does not contain Oxygen Step 2: If it does not contain Oxygen, like HCl (Hydrogen Chloride), which contains an "-ide" ion combine the two (Hydrogen Chloride) to create Hydrochloride Acid Step 3: The ending of Hydrochloride Acid is incorrect so replace the "-ide" with "-ic" to create Hydrochloric Acid
How to name Acids that end in -ITE
Step 1: Examine the Formula and see if it contains Oxygen and is aqueous Step 2: If it contains Oxygen and is aqueous, like H₂SO₄(Hydrogen Sulphite), which contains an "-ite" ion the -ite will be replaced with -ous Step 3: Since the a state of matter is given the acid will not begin with hydrogen instead it will become Sulphurous Acid
Bases and Salts
• Bases generally have OH on the right side of their chemical formulas • Salts typically don't have a H at the beginning or an OH at the end
How to measure Acidity with the Ph Scale
• Normal range of pH is from 0 to 14, with a pH of 7 being neutral • Solutions with a pH lower than 7 are acidic • Solutions with a pH greater than 7 are basic • Solutions with a pH of 7 are neutral • Hydrochloric acid in the stomach has a pH of 1, while concentrated hydrochloric acid (1M) has a pH of 0 so the concentrated HCl is more acidic • It is possible to have an extremely acidic solution with a pH lower than 0 (negative pH value), or an extremely basic solution with a pH greater than 14 • The pH paper will display a certain colour when immersed in a solution. When that colour is matched to a colour chart for the pH paper, the solution's pH can be approximated **Data Booklet Includes Chart**
Inorganic Compounds
• a inorganic compound is a compound that generally do not contain carbon and are not classified as organic • inorganic compounds can be ionic or molecular based on the bonds that join them together internally • some of these compounds contain carbon atoms, but the carbon is not considered present in a high percentage ex. Carbon Dioxide, Carbon Monoxide and Ionic Carbonates
How to name Acids that end in -ATE
Step 1: Examine the Formula and see if it contains oxygen and is aqueous Step 2: If it contains Oxygen and is aqueous, like HNO₃(aq) (Hydrogen Nitrate) , which contains an "ate" ion so the -ate will be replaced with -ic Step 3: Since the a state of matter is given the acid will not begin with hydrogen instead it will become Nitric Acid
Chemical Indicators
Chemical Ind. Acids Base methyl orange red yellow methyl red red yellow bromothymol blue yellow blue litmus red blue phenolphthalein colourless pink indigo carmine blue yellow **Data Booklet Includes Chart**
Inorganic Molecular Compounds
Compounds in this class are: • inorganic, so they contain little (at least not in a high percentage) or no carbon • molecular, so they have a non-metal bonded to a non-metal to form molecules • Some examples of inorganic molecular compounds that are quite common: water (H₂O), ammonia (NH₃), carbon dioxide (CO₂, considered low percentage carbon), and laughing gas (N₂O) • Most inorganic compounds are ionic
General Properties of Acids
• conduct an electric current • cause chemical indicators to change colour (for ex. blue litmus turns red or Phenolphthalein is colourless in a acidic solution) • react with certain metals when dissolved in solution to produce hydrogen ions (H⁺) and release Hydrogen Gas (H₂) • taste sour ex. Lemons, Limes and Vinegar • many will burn skin ex. Sulphuric Acid (Battery Acid) • can corrode metals • conductive • pH less than 7
General Properties of Bases
• conduct an electric current • cause chemical indicators to change colour (for example, red litmus turns blue or Phenolphthalein is colourless in slightly basic solutions and pink in moderate to strongly basic solutions) • do not react with certain metals to produce hydrogen gas • taste bitter ex. Quinine in Tonic Water • feel slippery • many will cause skin to burn ex. Sodium Hydroxide • does not corrode or react with metals • conductive • pH more than 7 • form hydroxide (OH⁻) ions when dissolved in solution
General Properties of Salts
• conduct an electric current • have no effect on chemical indicators (for ex.red/blue litmus does not change colour) • do not react with certain metals to produce hydrogen gas
Inorganic Ionic Compounds
• studies led to what is understood as the Arrhenius definitions of acids, bases, and salts: - acids are substances that release H ions in solution - bases are substances that release OH ions in solution - salts are substances that release positive ions and negative ions other than H and OH in solution. • It is a common understanding that, unless otherwise stated, the term "solution" means that substances are dissolved in water - water solutions often are referred to as aqueous solutions and have the designation of (aq). For ex. NaCl (aq) represents a solution formed when sodium chloride (table salt) is dissolved in water.
