Study Guide_Y10_Acids and Bases 2010

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Year 10 Science Study Guide
Acids and Bases
Introduction to this unit
This unit is important because:
We are used to grouping objects or substances together that have similar physical properties. We can
also group substances that have similar chemical properties – for example the families of ‘acids’ and
‘bases’. These families of chemicals are found in many places, including at home, in nature and in our
bodies.
Specific Learning Outcomes
By the end of this unit…
…all students should be able to …
 Distinguish between pure substances, elements, mixtures
and compounds in the context of acids and bases.
 Name two common laboratory acids and two common
laboratory bases.
 Describe the general reaction between common laboratory
acids with most metals and metal carbonates.
 Discuss the use of acids and bases in household substances
in terms of physical and chemical properties.
…most students should be able to…
1. Identify substances as acidic, basic or neutral on the basis of:
a) Results of testing with common indicators (universal indicator and litmus).
b) Common physical (feel, taste) and chemical properties (i.e. reactions).
2. Relate the degree of acidity or basicity/alkalinity of a substance to the pH scale.
3. Describe some common substances found at home and in the laboratory* as either acidic or
basic.
4. Describe the arrangement of electrons in energy levels or shells.
5. Explain that atoms react (change) if they can so they achieve full electron shells.
6. Describe the formation of metal ions and common monatomic negative ions in terms of loss
or gain of electrons.
7. Write the ionic formula of compounds involved in acid-base reactions given a reference table
of named ions.
8. Use the context of reactions to explain ion formation and formulae of compounds
9. Describe and write word equations for the reactions (reactants and products) of acids with:
a. Metals; and
b. Metal carbonates
c. Bases (limited to hydroxides of metals), i.e. neutralisation.
10. Write chemical symbol equations to describe a reaction.
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 Link the properties of acids and bases to how they are used in society or occur in nature e.g. of
contexts, soil pH, cosmetics, swimming pool chemistry, toothpaste, acid rain, insect bites,
cooking.
Extension
…in addition, some students will progress further and will be able to:




Relate the pH scale to the relative concentrations of hydrogen and hydroxide ions present in a
solution.
Explain neutralisation in terms of hydrogen and hydroxide ions in water.
Balance a chemical symbol equation to describe a reaction.
Investigate at least one factor that affects the rate (speed) of an acid-base reaction (surface
area, concentration or temperature).
Science Essential Vocabulary
Through the activities in this unit you should be able to define and understand:
Acid/acidic
Base/basic
Alkali/alkaline
Neutral
Indicator
Litmus
Universal Indicator
pH
Concentrated
Dilute
React
Reaction
Reactant(s)
Product(s)
Mixture
Element
Compound
Pure Substance
Neutralisation
Salt(s)
Ion(s)
Positive ion
Negative ion
Electron(s)
*Common lab acids
Hydrochloric acid
Sulfuric acid
*Common lab bases
Sodium hydroxide
Ammonium solution
Carbonates
Sodium carbonate
Calcium carbonate
*Sodium hydrogen carbonate
(baking soda)
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Names of metals and metal
ions:
Sodium
Lithium
Calcium
Magnesium
Aluminium
Zinc
Iron
Copper
Names of negative ions:
Chloride
Sulfate
Hydroxides
Carbonate
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