Thick liquid consisting of hundreds of combustible hydrocarbons with small amounts of sulfur, oxygen, and nitrogen Dead organic matter from plants and animals piled up on the sea floor hundreds of millions of years ago Who has it? Middle East-Saudi Arabia, Iraq, Kuwait, Iran, United Emigrates, Venezuela

OPEC-ORGANIZATION OF PETROLEUM EXPORTING COUNTRIES

Types of Energy? Energy Kinetic energy (E K ) Potential energy (E P ) Energy due to motion Energy due to position (stored energy) Energy is the Ability To Do Work

Electrical

What is Mechanical Energy? oEnergy due to a object ’ s motion (kinetic) or position (potential). The bowling ball has mechanical energy. When the ball strikes the pins, mechanical energy is transferred to the pins! What is Light Energy? Light energy is electromagnetic radiation, particularly radiation of a wavelength that is visible to the human eye. The movement of photons. Includes energy from gamma rays, x-rays, ultraviolet rays, visible light, infrared rays, microwave and radio bands

What is Electrical Energy? oEnergy caused by the movement of electrons o Easily transported through power lines and converted into other forms of energy What is Chemical Energy? Energy that is available for release from chemical reactions. The chemical bonds in a matchstick store energy that is transformed into thermal energy when the match is struck.

What is Heat Energy? o The heat energy of an object determines how active its atoms are. This causes a change in temperature. A hot object is one whose atoms and molecules are excited and show rapid movement. A cooler object's molecules and atoms will show less movement.

Nuclear energy is the energy stored in the nucleus of an atom. Submarines, power plants, and smoke detectors all use nuclear energy. Nuclear power plants use uranium, a radioactive element, to create electricity.

THERMOCHEMISTRY The study of heat released or required by chemical reactions Fuel is burnt to produce energy - combustion (e.g. when fossil fuels are burnt) CH 4 (g) + 2O 2 (g) CO 2 (g) + 2H 2 O(l) + energy

Reactions All chemical reactions either release or absorb heat Exothermic reactions: Reactants products + energy as heat e.g. burning fossil fuels e.g. photosynthesis Reactants + energy as heat products Endothermic reactions:

Endothermic and exothermic reactions Step 1: Energy must be SUPPLIED to break bonds: Step 2: Energy is RELEASED when new bonds are made: A reaction is EXOTHERMIC if more energy is RELEASED then SUPPLIED. If more energy is SUPPLIED then is RELEASED then the reaction is ENDOTHERMIC

Measuring Heat reaction Exothermic reaction, heat given off & temperature of water rises Endothermic reaction, heat taken in & temperature of water drops

Vaporization Energy has to be supplied to a liquid to enable it to overcome forces that hold molecules together endothermic process Melting Energy is supplied to a solid to enable it to vibrate more vigorously until molecules can move past each other and flow as a liquid endothermic process Freezing Liquid releases energy and allows molecules to settle into a lower energy state and form a solid exothermic process (we remove heat from water when making ice in freezer)

Energy level diagrams Energy level Reaction progress Activation energy Energy given out by reaction Using a catalyst might lower the activation energy Reactants Products

Exothermic vs endothermic: EXOTHERMIC – more energy is given out than is taken in (e.g. burning, respiration) ENDOTHERMIC – energy is taken in but not necessarily given out (e.g. photosynthesis)

Burning Methane CH 4 + 2O 2 2H 2 O + CO 2 Methane Carbon dioxide Water Oxygen

Bond Energies C-H = 435 Kj O=O = 497 Kj Total for breaking bonds = 4x x497 = 2734 KJ/mol H-O = 464 Kj C=O = 803 Kj Total for making bonds = 2x x464 = 3462 KJ/mol Total energy change = = -728 KJ/mol

Drawing this on an energy diagram: 2734 Kj 3462 Kj More energy is given out (3462) than is given in (2734) – the reaction is EXOTHERMIC. The total (“nett”) energy change is –728 Kj. An endothermic reaction would have a positive energy change Kj

ENERGY CONVERSIONS EXAMPLE-PRODUCING POWER from Coal FOSSIL FUELS (POTENTIAL ENERGY) POWER PLANT (THERMAL ENERGY) GENERATOR TURBINE (MECHANICAL ENERGY) ELECTRICAL TRANSMISSION LINES (ELECTRICAL ENERGY) Law of Conservation of Energy-energy is not created nor destroyed