Thermodynamics and Energy Principles

Energy

• The capacity to do work or create change.
• Two types:
  • Potential energy: Stored energy.
  • Kinetic energy: Energy of motion.
• Law of Thermodynamics: Energy cannot be created or destroyed, only transformed.
  • In every transformation, some energy is released as heat.
  • The quality of energy degrades during transformation, in line with the second law of thermodynamics.
  • Entropy (disorder or randomness) increases in every natural process.

Electricity

• Most common form of energy used by humans.
• Generated by converting kinetic energy into electrical energy.
• Often involves a generator with magnets and coils of metals like copper and aluminum, where electrons are loosely held.
• Moving a magnet around the metal coils pushes the electrons, creating an electric current.

Non-Renewable Energy Sources

• Coal:
  • Readily combustible sedimentary rock, formed from dead plants over a long time.
  • Most abundant fossil fuel.
• Major Air Pollutants:
  • Carbon Monoxide (CO): Colorless, odorless, toxic gas formed from incomplete combustion.
    • Major sources: Vehicle exhaust, forest fires, smoking.
    • Reduces blood's ability to transport oxygen, causing health problems.
  • Carbon Dioxide (CO2): Colorless, odorless gas, primarily due to natural carbon cycle.
    • Human activities (fossil fuels, deforestation) contribute to increased CO2 levels.
    • A significant factor in global warming.
  • Nitrogen Oxides (NOx): A group of gases including NO and NO2.
    • Contribute to smog formation.
    • Formed during combustion processes and by lightning and bacterial activity.
  • Nitrous Oxide (N2O): Greenhouse gas also emitted by fertilizers and animal waste.
    • Harmful to the environment and human health.
  • Sulfur Dioxide (SO2): Colorless gas with an irritating odor, mostly from human sources.
    • Contributes to acid rain and respiratory problems.
  • Particulates: Fine particles and liquid droplets that linger in the air.
    • Contribute to respiratory problems, and some are toxic, like lead and cadmium.
  • Ozone (O3): A highly reactive gas found in smog, damaging to respiratory health and plants.
  • Volatile Organic Compounds (VOCs): Gases emitted from natural and human sources, including some industrial chemicals.
• Climate Change:
  • Fossil fuel burning releases CO2, a major contributor to global warming.
  • Human activities are causing the Earth to warm at an unprecedented rate, leading to significant environmental changes.

Paris Agreement

• International agreement adopted in 2016 to address climate change.
• Aims to limit global temperature increases to well below 2 degrees Celsius, ideally 1.5 degrees.
• Countries set their own targets for reducing CO2 emissions.
• United States has withdrawn from the agreement.

Hydrosphere

• Water:
  • Only 1% of the world’s water is accessible for human consumption.
  • 68.1% is ice, 30% is groundwater, and only 1.2% is surface water.
  • Majority of liquid freshwater is hidden underground.
• Water Use:
  • Domestic use: 11%
  • Industry: 19% (90% of electricity generation is water-intensive)
  • Agriculture: 70%
• Blue Water and Green Water:
  • Terms referring to water used in agriculture.
  • Green Water: Moisture retained in soil from rainfall.
  • Blue Water: Surface water (rivers, lakes) and groundwater used for irrigation.
• Virtual Water: Water embedded in products we consume, often hidden from our awareness. - 90% of our water consumption is virtual and invisible to us.

Groundwater

• A major source of freshwater.
• Replenished slowly from precipitation infiltrating through the soil.
• Zone of Saturation: Underground area where spaces are filled with water.
• Water Table: Top of the groundwater zone.
• Aquifers: Underground layers of rock or sediment that store and transmit groundwater.
  • Can be confined by impermeable layers.
  • Recharge rates are usually slow.

Groundwater Contamination

• Groundwater can be contaminated by pollutants, like toxins and chemicals.
• Pollutants can be long-lasting due to slow flow, low dissolved oxygen, and small populations of decomposing bacteria.
• Remediation methods include:
  • Extraction wells and treatment.
  • Vapor extraction.
  • Bioremediation.
  • Permeable treatment beds.

Hydrologic Cycle

• Continuous movement of water on, above, and below the Earth's surface, driven by solar energy and gravity.
• A key for water recycling and purification.
• Human activities can overload the cycle, causing water shortages and pollution.
• Wetlands and forests play important roles in storing and releasing water.

Water Pollution Sources

• Oxygen demanding waste is caused by dead plant and animal matter, commonly called organic matter, which decays over time. This decay process is carried out by bacteria that need oxygen to survive. If there is too much bacterial activity, the oxygen in the water can be depleted to dangerously low levels, leading to the death of fish and other organisms. The amount of oxygen consumed by this process is called Biochemical Oxygen Demand (BOD). High BOD indicates a large amount of decaying organic matter in the water.

• Pathogenic Organisms are microscopic organisms that can cause diseases like cholera, typhoid, hepatitis, and dysentery. They are significant biological pollutants that can be spread through contaminated water. The presence of fecal coliform bacteria in water is a common indicator of biological pollution. Although typically harmless, fecal coliform bacteria reside in human intestines and are found in human waste.

• Nutrients released by human activities can contribute to water pollution. Excess amounts of phosphorus and nitrogen, often from fertilizers, detergents, and sewage treatment plants, can cause problems. These nutrients lead to cultural eutrophication, a process where excess nutrients cause excessive growth of algae and plants, creating a dense layer on the water surface and blocking sunlight. This, in turn, inhibits the growth of underwater plants and leads to a cycle of death, decomposition, and oxygen depletion.

• Oil spills, particularly from tanker accidents, can severely contaminate water sources.

• Toxic substances such as heavy metals and synthetic organic chemicals can poison aquatic organisms.

Geosphere

• The geosphere encompasses rocks, minerals, the abiotic parts of soils, and fossilized animal remains.

• It involves the rock cycle, with continuous recycling of rocks between sedimentary, igneous, and metamorphic forms.

• Sedimentary rocks are formed from the weathering and transport of existing rocks, followed by deposition, cementation, and compaction.

• Igneous rocks are formed by the cooling and crystallization of molten rock.

• Metamorphic rocks are formed when heat or pressure are applied to other types of rocks.

• Tectonic plates, the primary driving force behind geological processes, are responsible for shaping the Earth's surface, leading to the creation of mountains, volcanoes, and ocean basins.

Soil

• Soil is a solid Earth material modified by physical, chemical, and biological processes to support plant life.

• Soil texture is determined by the relative proportions of sand, silt, and clay particles.

• Clay particles are the smallest, with a diameter less than 0.004 mm. They hold water and nutrients well due to their structure and composition.

• Silt particles have diameters from 0.004 to 0.063 mm. They feel like flour and can be easily dusted off when dry.

• Sand particles are the largest, with diameters ranging from 0.063 to 2.0 mm. They have a coarse texture that does not retain water or nutrients effectively.

• Soil color is influenced by organic matter content, drainage, and aeration.

Essential Nutrients for Plant Growth

• Plants require 17 essential elements, of which 14 are obtained from soil.

• Nitrogen is crucial for forming plant proteins and chlorophyll, and plays a crucial role in amino acids, nucleic acids, and coenzymes.

• Phosphorus is used for forming DNA and RNA, storing and transferring energy, promoting early growth and root development, and contributing to flowering and fruiting.

• Potassium is essential for sugar translocation, starch formation, and efficient water use through its role in opening and closing leaf stomata.

Sustainable Soil Management Practices

• Contour plowing involves plowing perpendicular to the slope of the land, which is more effective in reducing soil erosion caused by water runoff compared to traditional plowing methods.

• No-till agriculture completely eliminates plowing, which significantly reduces soil erosion and promotes sustainable farming practices.

• Terracing slopes involves creating flat areas for farming on steep slopes to prevent soil erosion, using retaining walls for support.

• Intercropping involves planting multiple crops together, a particularly effective method in areas with low human populations.

• Soil erosion is a significant problem in the Philippines due to the country's hilly terrain, heavy rainfall, and unsustainable land management practices.

• Prime agricultural lands, often situated near urban centers, require careful management to ensure their productivity remains for future generations.

Explore the fundamentals of thermodynamics through this quiz, which covers key concepts such as the definition of energy, its two main types, and the laws governing energy transformations. Understand the significance of heat release, the relationship between energy quality and entropy, and insights from the third law of thermodynamics concerning perfect crystals. Test your knowledge of these essential scientific principles!