8.1 – classifying inorganic compounds

Science 10

Mr. Francis

8.1 – CLASSIFYING INORGANIC COMPOUNDS

A WARMUP ACTIVITY…• Using the information in tables 1 and 2 on page 203, classify each compound below as

an acid, base, or salt based on its properties:

• HCl: reacts with metals, turns litmus paper red

• KBr: conducts electrical current, chemical indicators do not change color

• NH3: turns methyl red indicator yellow

• NaNO3: does not react with metals; conducts electric current; phenolphtalein indicator remains colorless

• HNO3: turns indigo carmine from yellow to blue

8.1 – THE KEY CONCEPT• Compounds that have a high percentage of carbon by mass are classified as organic

compounds, otherwise they are considered to be inorganic compounds

CLASSIFYING INORGANIC COMPOUNDS• Inorganic compounds can be molecular or ionic based on the type of bonds that hold the

components (elements) together

• Inorganic ionic compounds can be classified as acids, bases, or salts depending on their properties

CLASSIFYING INORGANIC COMPOUNDS• Inorganic compounds can be classified as either molecular (a few) or ionic (most)

CLASSIFYING INORGANIC COMPOUNDS• Inorganic molecular compounds can be classified as either acids, bases, or salts

• Salts are substances that release positive and negative ions other than H + and OH- in solution

• For example sodium chloride, NaCl

• Acids are substances that release H+ ions in solution

• Bases are substances that release OH- ions in solution

CLASSIFYING INORGANIC COMPOUNDS

CLASSIFYING INORGANIC COMPOUNDS• Acids have the following properties:

• Sour taste

• Conduct an electrical current

• Causes chemical indicators to change colour

• Reacts with some metals to produce hydrogen gas (H2)

CLASSIFYING INORGANIC COMPOUNDS• Bases have the following properties:

• Slippery feeling, bitter taste

• Conducts an electric current

• Causes chemical indicators to change colour

• Does not react with acids to create hydrogen gas

CLASSIFYING INORGANIC COMPOUNDS• Salts have the following properties

• Salty taste

• No effect on chemical indicators

• Does not react with metals to make hydrogen gas

CLASSIFYING INORGANIC COMPOUNDS• Some common indicators are

• Methyl Red

• Bromothymol Blue

• Phenolphtalein

CLASSIFYING INORGANIC COMPOUNDS• Acidity is the measure of the relative amounts of H+ and OH- in a solution and is often

measured on a pH scale

CLASSIFYING INORGANIC COMPOUNDS• Pure water is always neutral (pH 7 ) and has equal H+ and OH- ions

• Acids have a greater number of H+ ions

• The more H+ ions, the more acidic the solution

• The more OH- ions, the more basic (or alkali) the solution

• Adding salt does not change the pH because it doesn’t change the amount of H + and OH -

ions

CLASSIFYING INORGANIC COMPOUNDS• The pH scale uses a logarithmic scale – each whole number is 10 times greater than the

number before

• pH 4 is 10 times more acidic than pH 5

• pH 3 is 100 times more acidic than pH 5

• Some common acids are hydrochloric acid (HCl), nitric acid (HNO 3), and sulphuric acid (H2SO4)

NAMING ACIDS…..

• Complete the worksheets

• Naming Acids

• You have 10 minutes

NAMING SALTS• To name salts, you use your ionic naming rules

• Salts always contain positive (metal) and negative (non-metal) ions

ASSIGNMENT• pH worksheet from after the test

• Naming acids worksheet

• Lab – Acids, Bases, and salts

• P. 209 Q 3,4,6,7,8,9,16