Chemistry Reviewer - PDF

CHEMISTRY REVIEWER ▪ GEOTHERMAL ENERGY - is heat derived within the sub-surface of the earth. Water and/or steam carry...

CHEMISTRY REVIEWER ▪ GEOTHERMAL ENERGY - is heat derived within the sub-surface of the earth. Water and/or steam carry the geothermal energy to the Earth's surface. ENERGY: Depending on its characteristics, geothermal energy - is the ability to do work. can be used for heating and cooling purposes or be harnessed to generate clean electricity. TWO TYPES OF ENERGY: ▪ WIND ENERGY - (or wind power) refers to the ▪ POTENTIAL ENERGY (STORED) – is the energy process of creating electricity using the wind, or air stored within an object, due to the object’s position, flows that occur naturally in the earth's atmosphere. arrangement or state. ▪ BIOMASS ENERGY - is energy generated or ▪ KINETIC ENERGY (WORKING) – is the energy that produced by living or once-living organisms. The it possesses due to its motion. It is defined as the most common biomass materials used for energy are work needed to accelerate a body of a given mass plants, such as corn and soy, above. The energy from rest to its stated velocity. from these organisms can be burned to create heat or converted into electricity. ENERGY COMES IN DIFFERENT FORMS: ▪ HEAT ENERGY (THERMAL) – is a form of energy ▪ HYDROPOWER ENERGY - Flowing water creates transfer. Unlike temperature, which refers to the energy that can be captured and turned into energy contained within a system, heat refers to the electricity. This is called hydroelectric power or transfer of that energy between systems. hydropower. The most common type of hydroelectric power plant uses a dam on a river to store water in a ▪ LIGHT ENERGY (RADIANT) – is a form of reservoir. electromagnetic radiation. Light consists of photons, NON – RENEWABLE ENERGY - an energy source that which are produced when an object’s atoms heat up. cannot easily replenished. Light travels in waves and is the only form of energy visible to the human eye. ▪ Petroleum products MOTION ENERGY (KINETIC) - also known as mechanical energy; is the energy stored in moving ▪ Hydrocarbon gas liquids objects. As the object moves faster, more energy is stored. It is also the sum of potential and kinetic ▪ Natural gas energy in an object that is used to do work. ▪ Nuclear energy ▪ ELECTRICAL ENERGY - is a form of energy resulting from the flow of electric charge. Energy is ▪ Coal the ability to do work or apply force to move an object. In the case of electrical energy, the force is ELECTROCHEMICAL ENERGY - Defined as “the energy electrical attraction or repulsion between charged which converts electrical energy to chemical energy and vice particles. versa.” ▪ This includes reactions transferring ▪ CHEMICAL ENERGY - is the potential of a chemical electrons, redox reactions (reduction- oxidation). substance to undergo a transformation through a Reduction, when a substance receives one electron. chemical reaction to transform other chemical Oxidation when a substance gives away one substances. electron. ▪ NUCLEAR ENERGY - is the use of nuclear reactions that release nuclear energy to generate heat, which HOW ELECTROCHEMICAL ENERGY WORKS? – It works most frequently is then used in steam turbines to in fuel cells, photo electrochemical, batteries and super produce electricity in a nuclear power plant. capacitors. ▪ GRAVITATIONAL ENERGY - is energy associated with gravity. It is the potential energy stored by an object because of its higher position compared to a ELECTROCHEMICAL CELLS – a device that produces an lower position. electric current from energy released by a spontaneous redox reaction. This kind of cell includes the galvanic, or voltaic. ENERGY SOURCES ARE DIVIDED INTO TWO GROUPS: ▪ It was named after Luigi Galvani and Alessandro Volta. It was developed during the late 18th century. RENEWABLE ENERGY - an energy source that can be easily replenished. DANIELL CELL – It was named after its inventor John Fredric ▪ SOLAR ENERGY - is radiant light and heat from the Daniell on 1836. It consists of a zinc rod dipping in a solution Sun that is harnessed using a range of ever-evolving of zinc sulphate, connected by a wire to a copper rod dipping technologies such as solar heating, photovoltaics, in a copper sulphate (II) solution. solar thermal energy, solar architecture, molten salt power plants and artificial photosynthesis. VOLTAIC CELL - is an electrochemical cell that uses a coating of nickel oxide forms on the nickel chemical reaction to produce electrical energy. It processes electrode. chemical potential energy to electrical energy. ELECTROLYTIC and ELECTROLYSIS CELLS – is a process whereby electrical energy is converted directly into chemical energy is called electrolysis; i.e., an electrolytic process. MAIN COMPONENTS OF ELECTROLYSIS: ▪ ELECTROLYTE - a substance containing free ions that carry electric current ▪ DIRECT CURRENT (DC) SUPPLY – provides the energy necessary to create or discharge the ions in the electrolyte. ▪ TWO ELECTRODES – an electrical conductor that provides the physical interface between the electrical circuit providing the energy and the electrolyte. ELECTROCHEMICAL ENERGY STORAGE - constitute an essential element in the development of sustainable energy technologies. Electrical energy generated from renewable resources such as solar radiation or wind provides great potential to meet our energy needs in a sustainable manner. BATTERIES - These devices store chemical energy and convert it into electrical energy through electrochemical reactions. Common types include lithium-ion batteries, lead- acid batteries, and nickel-metal hydride batteries. FUEL CELLS - generate electrical energy directly from a chemical reaction between a fuel (such as hydrogen, methanol, or natural gas) and an oxidizing agent (usually oxygen from the air). They are highly efficient and produce minimal emissions compared to combustion engines. KEY TERMS: ELECTROLYSIS - This process uses electrical energy to ▪ REDOX - A reversible chemical reaction in drive a non-spontaneous chemical reaction, such as splitting which one reaction is an oxidation and the water into hydrogen and oxygen gases. The produced reverse is a reduction. hydrogen can be used as a clean fuel for various applications. ▪ HALF CELL - Either of the two parts of an electrochemical cell containing an electrode and an electrolyte. SUPERCAPACITOR - Also known as electrochemical capacitors, supercapacitors store electrical energy by ▪ VOLTAIC CELL - A cell, such as in a separating positive and negative charges on the surface of battery, in which an irreversible chemical electrodes. They can deliver high power quickly and are used reaction generates electricity; a cell that for energy storage in devices like hybrid vehicles and cannot be recharged. renewable energy systems. ▪ EDISON BATTERY – is a simple, rechargeable cell invented by Thomas Edison. It consists of two metal electrodes, one made of iron, the other of nickel. During initial charging, a