8.1 – CLASSIFYING INORGANIC COMPOUNDS
Science 10
Mr. Francis
A WARMUP ACTIVITY…
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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:
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HCl: reacts with metals, turns litmus paper red
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KBr: conducts electrical current, chemical indicators do not change color
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NH3: turns methyl red indicator yellow
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NaNO3: does not react with metals; conducts electric current; phenolphtalein indicator
remains colorless
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HNO3: turns indigo carmine from yellow to blue
8.1 – THE KEY CONCEPT
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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
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Inorganic compounds can be molecular or ionic based on the type of bonds that hold the
components (elements) together
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Inorganic ionic compounds can be classified as acids, bases, or salts depending on their
properties
CLASSIFYING INORGANIC COMPOUNDS
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Inorganic compounds can be classified as either molecular (a few) or ionic (most)
CLASSIFYING INORGANIC COMPOUNDS
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Inorganic molecular compounds can be classified as either acids, bases, or salts
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Salts are substances that release positive and negative ions other than H + and OH- in
solution
• For example sodium chloride, NaCl
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Acids are substances that release H + ions in solution
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Bases are substances that release OH - ions in solution
CLASSIFYING INORGANIC COMPOUNDS
CLASSIFYING INORGANIC COMPOUNDS
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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 (H 2)
CLASSIFYING INORGANIC COMPOUNDS
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Bases have the following properties:
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Slippery feeling, bitter taste
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Conducts an electric current
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Causes chemical indicators to change colour
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Does not react with acids to create hydrogen gas
CLASSIFYING INORGANIC COMPOUNDS
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Salts have the following properties
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Salty taste
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No effect on chemical indicators
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Does not react with metals to make hydrogen gas
CLASSIFYING INORGANIC COMPOUNDS
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Some common indicators are
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Methyl Red
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Bromothymol Blue
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Phenolphtalein
CLASSIFYING INORGANIC COMPOUNDS
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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
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Pure water is always neutral (pH 7 ) and has equal H + and OH- ions
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Acids have a greater number of H + ions
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The more H+ ions, the more acidic the solution
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The more OH- ions, the more basic (or alkali) the solution
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Adding salt does not change the pH because it doesn’t change the amount of H + and OH ions
CLASSIFYING INORGANIC COMPOUNDS
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The pH scale uses a logarithmic scale – each whole number is 10 times greater than the
number before
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pH 4 is 10 times more acidic than pH 5
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pH 3 is 100 times more acidic than pH 5
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Some common acids are hydrochloric acid (HCl), nitric acid (HNO 3), and sulphuric acid
(H2SO4)
NAMING ACIDS…..
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Complete the worksheets
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Naming Acids
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You have 10 minutes
NAMING SALTS
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To name salts, you use your ionic naming rules
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Salts always contain positive (metal) and negative (non-metal) ions
ASSIGNMENT
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pH worksheet from after the test
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Naming acids worksheet
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Lab – Acids, Bases, and salts
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P. 209 Q 3,4,6,7,8,9,16