Climate change poses a fundamental threat to the places, species and peopleâs livelihoods WWF works to protect. To adequately address this crisis we must urgently reduce carbon pollution and prepare for the consequences of global warming, which we are already experiencing. WWF works to:
How does your air conditioner manage this? In a similar way to how your refrigerator manages to stays cold, but minus the insulated box. A nonflammable gas, known as Freon, undergoes an evaporation process again and again within most refrigerators in order to keep the temperature low. The same cycle is used for air conditioners. This is how it works: First, a compressor in your air conditioner compresses cold Freon gas. A small amount of oil is combined with the Freon gas to lubricate the compressor. When the Freon gas is compressed, its pressure rises, making it very hot.
The freon in air conditioners (home or car) and refrigerators changes from gas to a liquid and back to a gas, which then repeats. This is a physical change because the freon does not change its chemical makeup, just its state (liquid versus gas). A physical change is easily reversible.atching sugar burn allow you to witness hundreds of types of chemical reactions in a matter of seconds. The physical change you noticed is when the sugar reached its melting point (which is a physical property). Then the color change indicates a chemical reaction.