MT-CHM1-LEC-Lesson-3-Energy-1.0
RECALL OF PAST LESSON
Periodic Table
Definition: Tabular arrangement of chemical elements.
Organization: Based on atomic number, electron configuration, and recurring chemical properties.
Purpose: Systematic way to categorize and understand fundamental building blocks of matter.
Atomic Number and Structure
Atomic Number: Unique identifier for each element, representing the number of protons in the nucleus.
Groups and Periods:
Groups: Vertical columns sharing similar properties.
Periods: Horizontal rows detailing trends and relationships among elements.
Chemical Properties
Valence Electrons: Elements in the same group behave similarly due to similar valence electron counts.
Metallic vs Non-Metallic Properties:
Metals: Lustrous, good conductors, tend to lose electrons.
Non-metals: Lack metallic properties, often gain electrons in reactions.
Metallic and Non-Metallic Properties
Classification: Metals, non-metals, and metalloids based on chemical/physical characteristics.
Trends: Atomic size, ionization energy, electronegativity, and reactivity reflect trends across groups and periods.
Major Groups in Periodic Table
Main Groups: Alkali metals, alkaline earth metals, halogens, noble gases (Groups 1, 2, 13-18).
Transition Metals: Found in the d-block, known for multiple oxidation states and complex compound formation.
Lanthanides and Actinides: F-block elements located below the main table, notable for their unique properties.
Historical Development
Mendeleev's Periodic Law: Fundamentally arranged elements to predict properties of undiscovered elements.
ENERGY
Definition
Energy is the part of the universe capable of doing work.
Classification of Energy
Kinetic Energy:
Associated with motion; includes thermal energy linked to atom/molecule motion.
More thermal energy increases kinetic energy.
Potential Energy:
Stored energy based on the position within a system.
Includes chemical energy stored in bonds.
Sound Energy:
Produced through vibrations; travels as waves needing a medium (e.g., air, water).
Examples include voice, musical instruments, etc.
Radiant Energy:
Combination of heat and light energy; travels in waves.
Found in light bulbs, sunlight, etc.
Electrical Energy:
Produced by the movement of electrons.
Powers devices like TVs, radios, and household appliances.
Atomic Energy:
Generated from splitting atoms; releases significant energy.
Examples include nuclear power and atomic bombs.
Mechanical Energy:
Visible movement energy; associated with moving objects.
Includes machines and kinetic activities.
Transformation of Energy
Defined as changing energy from one form to another, a fundamental principle in energy studies.
CONSERVATION AND MEASUREMENT OF ENERGY
Conservation of Energy
Law: No energy is created or destroyed during transformations; total energy remains constant.
Measurement of Energy
Caloric Measurement:
1 calorie: energy needed to raise 1g of water by 1°C.
1 kcal = 1000 calories.
1 calorie = 4.184 Joules.
Important in nutrition (1 Cal = 1 kcal).
SUMMARY
Energy plays a crucial role in both inorganic and organic chemistry.
Energy changes during chemical reactions are fundamental for understanding molecular behavior and predicting chemical interactions.
REFERENCES
Stoker, H. Stephen (2013). Biological Chemistry(6th Ed). USA: Cengage Learning.
Bettelheim (2019). Introduction to General Organic, and Biochemistry(11th edition). Cengage Learning.