Chemical reactions

Topics

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Sample objectives

What this unit covers

• Physical and chemical changes: Recognize and differentiate between physical changes and chemical changes, and explain how they vary from one another.
• Rate of reaction: Explain how the rate of a reaction is influenced by factors such as the concentration of solutions, pressure of gases, surface area of solids, temperature, and the presence of a catalyst or enzyme.
• Rate of reaction: Recognize that a catalyst speeds up a reaction and remains unchanged after the reaction is complete.
• Reversible reactions and equilibrium: Recognize that certain chemical reactions can reverse, indicated by the symbol ⇌.
• Reversible reactions and equilibrium: Explain how altering conditions can influence the direction of a reversible reaction, specifically regarding: (a) the impact of heat on hydrated substances (b) the effect of adding water to anhydrous substances, limited to copper(II) sulfate and cobalt(II) chloride.
• Redox: Indicate the oxidation number of an element in a compound using Roman numerals.
• Redox: Describe redox reactions as processes that involve both oxidation and reduction occurring simultaneously.