C3.3 Calculating + explaining energy changes

Teacher recommended

?
View mindmap
  • C3.3 Calculating + explaining energy changes
    • Energy is transferred in chemical reactions because old bonds are broken and new are formed.
      • Endothermic processes- Energy must be supplied to break existing bonds.
        • In endothermic reactions the energy required is greater than the energy released when new bonds are formed. The extra energy needed is absorbed from the surroundings and the temperature falls.
      • Exothermic processes-Energy is released when new bonds are formed.
        • In exothermic reactions the energy released in bond formation is greater than the energy required in breaking old bonds. The left over energy is released into the surroundings and the temperature rises.
      • Bond Energy - the energy required to break a bond or amount of energy released when a bond is made.
      • Energy per Gram
        • Mass of fuel,g = initial mass of fuel - final mass of fuel
          • Energy per gram, J/g = Energy charge, J / Mass of fuel, g
      • Energy per Mole
        • Moles of each reactant, mol = Mass, g / Molar Mass
          • Energy per mol, J/mol = energy change, J / Moles, mol
    • Calculating energy of different fuels by burning
      • The amount of energy transferred from the burning fuel to the water in the calorimeter can be calculated if you know the mass of water heated and rise in temperature.
    • Fuel Cells
      • Fuels cells can produce electricity by: hydrogen + oxygen --> water
      • Advantages
        • Water is the only product and is clean
          • non-polluting
      • Disadvantages
        • Hydrogen is hard to store safely as it is explosive
        • Shorter driving range than traditional vehicles
        • Special, expensive engine needed
        • Requires expensive catalysts - e.g. platinum
        • Not many Hydrogen refueling stations
    • Current fuels
      • Ethanol
        • CO2
        • Land use
          • Crops not used for food
          • Fermentation for ethanol production uses a lot of energy
      • Petrol and diesel
        • CO2
        • Increases greenhouse effect
        • SO2 + NO
          • Acid rain

Comments

theresa thomas

Report

Theresa Thomas, from Omaha, is my name!

As I'm from Omaha, Nebraska, please remember to share this post if you find it. When attempting to trade cryptocurrencies online, I fell victim to scammers, and within two weeks, I was defrauded of $53,700 USDT. Fortunately, though, I was referred to Cyber Backers Consultants, a premier bitcoin recovery team that regularly analyzes the strategic methods used by cryptocurrency scammers to con various victims ON daily.

And Within 48 hours of my case being examined By cyber backers consultants, The cyber supporters Teams, who i had consulted on forensic checks, assisted me in getting all of the USDT I had been scammed out of my possession.

I highly employ cyber backers consultants and heartily suggest them to anyone who has fallen victim to a cryptocurrency scam, just like I did. And i use this opportunity to advice everyone out there to pls deviate from involving on online binary options, cryptocurrency, forex, and Ponzi schemes. AND if you are a victim of crypto scams pls contact:

[email protected] NOW!

Similar Chemistry resources:

C2
See all Chemistry resources »See all Energy of reactions/Exothermic and endothermic reactions resources »