Cellular Metabolism: Energy, Reactions, and Processes
Free Energy
Free energy is the thermodynamic quantity used to study biological processes and predict whether they are energetically favorable. It represents the energy capable of performing useful work under constant temperature and pressure. The sign of ΔG indicates the reaction’s behavior:
- ΔG < 0: The reaction is exergonic (energetically favorable), releasing free energy.
- ΔG > 0: The reaction is endergonic (energetically unfavorable), requiring free energy absorption.
- ΔG = 0: The system
Polymer and Ceramic Materials: Properties and Applications
To obtain a polymer in polymer chemistry, hundreds of thousands of monomer molecules are chemically bonded. This creates homopolymers. If the polymer chain is formed by the union of different monomers, copolymers are obtained. In polycondensation, chain growth occurs by chemical reaction between two functional groups, most often with the loss of a small molecule, such as water or hydrochloric acid. In polyaddition, chain growth occurs by continuous addition of the same type of small molecules that
Read MoreComprehensive Chemistry Notes
Chapter 1: Periodic Table
Mendeleev’s Periodic Table
Introduction, Definition, Physical Properties, Chemical Properties, Periods, Groups, Periodic Law, Periodicity, Vacant Spaces, Advantages, Disadvantages
Long Form Periodic Table
Periodic Table Definition, Periods, Periodic Trends, Periodicity, Groups, Group Trends, Blocks
Chapter 2: Hydrides
Introduction, Definition, Physical Properties, Uses
Chapter 3: Sodium and Its Compounds
Sodium (Na)
Occurrence: NaCl
Preparation: Principal, Diagram, Construction,
Read MoreUnderstanding Chemical Elements, Compounds, and Mixtures
Matter and Its Classification
What is Matter?
Matter is anything that occupies space. It exists in nature as pure substances and mixtures.
Classification of Matter
Matter can be classified into two main categories:
- Pure Substances: Each pure substance has a fixed composition and a unique set of properties.
- Mixtures: Mixtures are composed of two or more pure substances.
Pure substances can be further categorized into elements and compounds, while mixtures can be homogeneous or heterogeneous.
Pure Substances
Elements
A
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Science Education
Questions for Teachers about Teaching Models
Teachers should consider the following questions when planning science lessons:
- Who will lead the teaching?
- When will specific knowledge be transmitted?
- What knowledge will be transmitted?
- What content will be conveyed?
- What methodology will be used to transmit knowledge?
Historical Methods of Teaching Science
- Evolutionary Method
- Biographical Method
Evolutionary Method
This method involves explaining a scientific subject or phenomenon by starting
Read MoreAtomic Structure, Bonding, and Properties of Matter
1. The Nuclear Model of the Atom
Democritus proposed the concept of atoms. J. Dalton’s atomic theory stated that atoms were indivisible and unchanged by chemical processes.
1.1 The Gold Foil Experiment
E. Rutherford bombarded a thin gold foil with alpha rays. He expected all particles to pass through uniformly. However, some particles were deflected, demonstrating that:
- The atom has a central core (nucleus) containing most of its mass, including protons.
- Electrons revolve in concentric circular orbits