Early Start And Chapter 1 And Chapter 2 Flashcards
Endothermic
Formed with absorption of heat from surrounding
Breaks bonds (cold)
Smaller activation energy
Exothermic
Formed with release of heat to surroundings
Makes bonds (hot)
Enthalpy
Measurement of energy in a thermodynamic system
Fuel
Substance with stored energy released easily for use as heat or power. Material like coal oil and gas burned to produce power and heat
Activation energy
Minimum energy in which the reactant must have ti perform a specific reaction
Renewable
Energy from natural sources replenished more then consumed
Non renewable
Can’t be replenished in a short amount of time
Fossil fuel
Non renewable energy formed in earths crust containing carbon and hydrocarbon which can be burned for fuel
Over time in absence of heat pressure and oxygen chemical structures of organic matter result in formation of fossil fuel like crude oil and natural gas and coal
Biofuel
Renewable fuel from plants and animals that can substitute fossil fuels
Suggested to have less impact environment compared to fossil fuels
Plant used in generation of this is produced via photosynthesis, removing carbon dioxide from the atmosphere.
Biodiesel
Clean burning renewable diesel substitute
Energy content
Amount of heat produced by burning 1g of a substance
Energy value
Amount of heat released during combustion of a specific amount of
Distillation
Action of producing liquid by process of heating or cooling . Separating components of liquid mixture through selective evaporation and condensation
Types of fossil fuel and description
Coal: plant material made of carbon that is readily combustible to produce electricity and heat
Natural gas: found in deposits in earth crust used as it is a simpler process to convert to liquid increasing energy density, found in gas reservoirs and petroleum deposits.
Petrol: obtained from crude oil, propels vehicles and produce electricity
Types of biofuel and description
Biogas (mainly a gaseous mixture do co2 and ch4): produced by breakdown of organic material by anaerobic bacterial releasing it (broken to microorganisms by abscess of oxygen) , break down carbs, reduce greenhouse emmison fuel vehicles.
Bioethanol: alcohol made by microbial fermentation, environmental friendly and energy efficient. Produced by fermentation of starches and sugars accelerated via enzymes. Enzymes catalyse breakdown of these components into sugars which then are fermented to ethanol in the absence of oxygen.
Biodiesel (mixture of esters 0) : made by mixture of esters from soybean canola and palm oil, heat homes, generate electricity, Lowe energy content, environmental friendly. Renewable fuel produced by reaction with animal fat or or vegetable oil with small alchohol molecules such as methanol. The reaction is. Transesterification.
Photosynthesis reaction
Energy from sunlight used to produce co2 and h20 (endothermic)
Process by which green plants and other organisms use sunlight to make nutrients from carbon dioxide and water.
Endothermic.
The glucose are transported in the sap of a plant to the cell. It can combine to form the polymers starch and cellulose
Cellular respiration reaction
Glucose broken down in animals to produce heat from the body (exothermic)
Energy sources
Carbohydrates: large group of organic compounds containing hydrogen and oxygen used as structural materials and energy storage
Protein: large compounds composed of one or more long chains of amino acids
Fats and oils (lipid): class of organic compounds that are fatty acids or their derivative
Fermentation equation words
Glucose to lactic acid and energy
Enthalpy during reactions
Exotehrmic:
Negative
Endothermic:
Positive
Combustion process
Hydrocarbon with oxygen hass to carbon dioxide and water
Incomplete v complete combustion
Incomplete involves insufficient oxygen. Complete releases more energy as it takes oxidation of fuel to its limit therefore more pressure, heat and energy is released
Heat of combustion
Amount of heat released during process of oxidation or combustion (kj/mol)
Enthalpy of combustion
Heat energy when 1 mom of a substance burns completely with oxygen (kj/mol)
Difference between heat of combustion and Enthalpy
Heat of combustion is Enthalpy for combustion reaction. Enthalpy can be negative as if applies to exothermic as well (when energy is released it is negative)
Thermodynamic equations
Exothermic
Endothermic
Why are some kj per g and other per mol
Per g is when we don’t know the actual value
What happens to Enthalpy value when the thermodynamic equation is reversed
H changes between positive and negative as thermodynamic is one direction Exothermic and the other endothermic
Crude oil
Mixture of hydrocarbon molecules that are mostly alkaline, has no use as a fuel and needs to be separated via fractional distillation to extract the smaller part that can be used as a fuel.
Energy from food
Supplies energy to our bodies, provides material for growth and repair of tissue, provide materials for control of body process
Chlorophyll
Present on the leaf assist with collection of solar energy.
Green pigment responsible for the absorption of light to provide energy
Respiration
Chemical energy stored in glucose released for use by the body, converted to thermal chemical electrical and mechanical energy.
Photosynthesis and respiration connection
Act togethor to maintain stable balance of oxygen and co2. Equations work opposite (reactant for photosynthesis is teh product for respiration.
