Energy Flashcards
What is energy?
The ability to do work (exert a force over a distance)
What can energy be measured in?
- Joule
- calorie
- Calorie
- kWh
- BTU
How many joules are in 1 calorie?
1 cal = 4.19 J
How many joules are in 1 Calorie?
1 Cal = 1000 cal = 4190 J
How many kilojoules are in are in 1 kWh?
1 kWh = 3600 kJ
How many joules is in 1 BTU (heat)
1 BTU = 1054 J
Define: gross domestic product (GDP)
GDP measures the amount of goods and services a country produces in a year
Define: energy intensity
The energy used/GDP
How do you calculate energy intensity?
Country’s energy usage in a year / GDP
List some things that can contribute to a country having a low energy intensity
- High tech industries (use energy efficient methods)
- Rely on services more than goods (use less energy)
Why do developing nations tend to have higher energy intensities?
Because their economies tend to rely on natural resource technology that is less sophisticated and less efficient.
Why does Canada have a relatively high energy intensity?
Due to Canada’s high level of activity in mining petroleum and other natural resources as a result of our economy being industry based.
How does climate affect energy use?
Colder places need to burn more fossil fuels to stay warm, and hotter places need to burn more to stay cool.
How does economic activity affect energy use?
Making more goods and services requires energy (but services need less energy than goods)
How does population and development affect energy use?
Developed nations use more energy per capita
Define: input energy
The energy being put into an energy transformation process
Define: useful output energy
The useful energy that results from an energy transformation process
What is the formula for the efficiency of an energy transformation?
Efficiency % = (Output / Input) x 100
Define: fossil fuels
- Hydrocarbons that are used as fuel
- Derived from plants and animals that lived millions of years ago
Define: hydrocarbon
- An organic compound made up of carbon and hydrogen
Define: chemical potential energy
The energy stored in the chemical bonds of a substance
Define: non-renewable
A substance that can only be used once as it cannot be replenished in a short period of time
Define: radiant energy
Energy of electromagnetic radiation
How is the chemical potential energy stored in fossil fuels released?
During combustion reactions
What is the format of a combustion reaction?
Fuel + O2(g) = CO2(g) + 2H2O(g)
All combustion reactions are __________ reactions
All combustion reactions are exothermic reactions
In an exothermic reaction, the energy of the ________ must be less than the energy of the ___________
In an exothermic reaction, the energy of the products must be less than the potential energy of the reactants, as energy is released
What forms can the energy released during a combustion reaction be released as?
- Radiant energy (visible or IR light) can be emitted
- Kinetic energy of the particles can increase due to the increase in temperature
- Kinetic energy from warmer objects to cooler ones (heat)