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• Permafrost


  A layer of soil frozen for two years.
• A rise in temperature in permafrost

  Can lead to thawing, which may cause land subsidence, release of greenhouse gases like methane, disruption of ecosystems, and damage to infrastructure built on permafrost
• Catchment area


  A territory surrounding a waterway where all the surface runoff and groundwater drains into the same place
• Human activities such as deforestation, urbanization, agriculture, and industrial pollution


  Can lead to water pollution, habitat destruction, altered hydrological cycles, and loss of biodiversity in waterways within a catchment area
• Salinity


  A measure of the quantity of salt in a solution, typically expressed in parts per thousand (ppt)
• Salinity


  Increases the density of a solution because dissolved salts increase the mass of the solution without significantly increasing its volume
• Factors such as wind patterns, temperature gradients, the Coriolis effect, and variations in water density due to salinity and temperature differences influence ocean circulation
• Thermohaline circulation, driven by differences in water temperature and salinity, helps regulate global climate by distributing heat around the Earth, affecting regional climate patterns, and influencing weather systems
• Glaciers


  Large bodies of ice that move slowly over land
• Pack ice


  Floating ice sheets or chunks that form in polar regions and drift with ocean currents
• The melting of glaciers and pack ice


  Contributes to sea level rise, alters ocean salinity and temperature, affects ecosystems and wildlife, and can lead to changes in weather patterns
• Greenhouse effect


  The process by which greenhouse gases in the Earth's atmosphere trap heat from the sun, preventing it from escaping back into space, thus warming the planet
• Higher greenhouse gas concentrations

  Can lead to global warming, climate change, more frequent and severe events, melting glaciers, rising sea levels, and shifts in ecosystems and agriculture
• Technologies used to produce electricity using energy resources from the lithosphere, hydrosphere, and atmosphere

  • Solar panels (atmosphere)
  • Wind turbines (atmosphere)
  • Hydroelectric dams (hydrosphere)
  • Geothermal power plants (lithosphere)
  • Fossil fuel power plants (lithosphere)
• Using energy resources from the lithosphere, hydrosphere, and atmosphere

  Can lead to air and water pollution, habitat destruction, deforestation, greenhouse gas emissions, climate change, and depletion of non-renewable resources
• Concentration


  Can be expressed in various units such as grams per liter (g/L), percent mass by mass (%m/m), percent mass by volume (%m/V), or parts per million (ppm)
• pH scale


  Measures the acidity or alkalinity of a solution, ranging from 0 to 14, with 7 being neutral. Values below 7 indicate acidity, while values above 7 indicate alkalinity. The scale is logarithmic, meaning each whole number change represents a tenfold change in acidity or alkalinity.
• You can determine acidity, basicity, or neutrality based on the presence of acidic or basic functional groups in the molecular formula. Acids donate protons (H⁺ ions), bases accept protons, and neutral substances neither donate nor accept protons.
• Ion


  An atom or molecule that has gained or lost one or more electrons, resulting in a positive or negative electrical charge
• The charge of a monatomic ion typically corresponds to the number of electrons gained or lost to achieve a stable electron configuration, which is determined by the element's position in the periodic table and its valence electrons
• Aqueous solutions conduct electricity


  By the electrolytic dissolution of solutes, which produce mobile ions capable of carrying electric charge
• Solutions containing ionic compounds or strong acids and bases tend to conduct electricity, while pure water and non-electrolyte solutions typically do not conduct electricity
• Combustion


  A rapid chemical reaction between a fuel and an oxidizing agent (typically oxygen) that releases heat and light energy, producing flame and often generating products such as carbon dioxide and water vapor
• Fire triangle


  Represents the three essential components for combustion: an oxidizing agent (usually oxygen), fuel, and a certain ignition temperature. Combustion occurs when these three elements are present in the right proportions.
• Photosynthesis


  6 CO₂ + 6 H₂O → C₆H₁₂O₆ + 6 O₂
• Respiration


  C₆H₁₂O₆ + 6 O₂ → 6 CO₂ + 6 H₂O + Energy (ATP)
• Acid-base neutralization reactions


  • Reaction between hydrochloric acid (HCl) and sodium hydroxide (NaOH) to produce sodium chloride (NaCl) and water (H₂O)
• Acid-base neutralization reaction products

  A salt and water
• The law of conservation of mass states that the total mass of reactants in a chemical reaction is equal to the total mass of products, meaning that mass is neither created nor destroyed in a chemical reaction, only rearranged
• In the particle model, the number and types of atoms remain constant before and after a chemical reaction, illustrating the conservation of mass
• Balancing a chemical equation

  Involves adjusting the coefficients of reactants and products so that the same number of each type of atom appears on both sides of the equation, satisfying the law of conservation of mass
• Groups


  Columns of elements with similar chemical properties
• Periods


  Rows of elements with increasing atomic number and similar electron configurations
• Common characteristics of a group include similar valence electron configurations, reactivity patterns, and physical properties
• Rutherford-Bohr atomic model


  Depicts electrons orbiting the nucleus in discrete energy levels or shells, similar to planets orbiting the sun, with each shell having a specific energy level and capacity for electrons
• Atoms with atomic numbers greater than 20 may have additional electron shells beyond those shown in typical Bohr diagrams. They can be recognized by their electron configurations and position in the periodic table
• Proton


  Positive charge
• Neutron


  No charge (neutral)
• Electron


  Negative charge
• Objects with similar electrical charges


  Repel each other due to the electrostatic force