7.1 Chemical Reactions Study Notes

Overview of Chemical Reactions

7.1.1 Introduction

  • Definition of Chemical Reactions: Fundamental processes that all living beings rely on for energy transformation, involving the transformation of reactants into products.

Importance in Living Organisms

  • Respiration:
      - Also known as cellular respiration.
      - Converts oxygen ( ext{O}_2) and sugars into:
        - Carbon dioxide ( ext{CO}_2)
        - Water ( ext{H}_2 ext{O})
        - Energy essential for survival.

  • Photosynthesis:
      - Chemical reactions in plants that transform carbon dioxide and water into sugars and nutrients (e.g., proteins and starch).

Topics to be Investigated

  • Recognition of when a chemical reaction occurs.

  • Rearrangement of atoms from reactants to products.

  • Energy considerations in reactions:
      - Importance of energy stored in reactants and products.
      - Evaluation of whether a reaction releases heat or requires heat.

  • Types of chemical reactions and their applications in daily life.

  • Extraction of naturally occurring elements from compounds.

Environmental Considerations

  • Discussion of by-products of reactions:
      - Potential side effects and damage to the environment.

  • Role of chemistry in modifying processes to enhance safety and environmental sustainability.

7.1.2 Questions to Consider About Chemical Reactions

  1. Do chemical reactions only occur in a laboratory setting?

  2. How do atoms behave during chemical reactions?

  3. Other than energy, what is conserved during chemical reactions?

  4. How can one determine the occurrence of a chemical reaction?

  5. What methods are there to extract elements from their compounds?

  6. In what ways can we mitigate environmental damage caused by chemicals?

7.1.3 Science Inquiry

  • Modeling Chemistry:
      - Models serve to clarify the nature of chemical reactions, illustrating the principle of matter conservation.
      - Assist chemists in explaining observations related to reactions.

Inquiry Questions

  1. a. Identify household chemicals used for cleaning and the best storage practices.
       b. What types of reactions do household chemicals undergo?
       c. What chemical reactions occur within the human body?

  2. Regarding green chemistry:
       a. Are all chemical reactions unsafe?
       b. Can a deeper understanding of reactions lead to solutions for environmental challenges?

Investigation 7.1: Baking Soda and Vinegar Reaction

  • Aim: Observe the chemical reaction between baking soda (sodium bicarbonate) and vinegar (acetic acid) while exploring its cleaning properties.

  • Resources: Links or instructions provided through the eWorkbook.

Resources & Activities

  • eWorkbook Topics:
      - Topic 7 overview: eWorkbook (ewbk-12446)
      - Student Learning Matrix: eWorkbook (ewbk-12448)
      - Starter Activity: eWorkbook (ewbk-12449)

  • Solutions:
      - Topic 7 Solutions (sol-1140)

  • Practical Investigation:
      - Topic 7 Practical Investigation eLogbook (elog-2319)

Assessment

  • Pre-Test:
      - A series of questions (Q1-Q15) assessing prior knowledge of chemical reactions and associated concepts.