Question

What is the best description of an isolated system?

Answer 1

What does it mean to be isolated? All that means is to be cut off. There are open systems and isolated (closed) systems. So when your system is isolated, it's just cut off from the rest of the universe and heat, matter, whatever can't get in or out.

Answer 2

Both energy and mass are conserved -- do not change.

Answer 3

Although true Carl, this is true for all systems and isn't unique to a closed system. In other words, mass and energy can not be created or destroyed in an open system.

Answer 4

an ideal thermoflask is an isolated system

Answer 5

Nonense, Kainui. An "open system" is one that by definition can exchange both energy and mass with its environment, like an uninsulated cup of hot coffee -- which your hand will tell you rapidly loses heat, i.e. energy, to the surroundings -- or like an open glass of water on the counter of a house in the desert, which will rapidly lose mass through evaporation.

You may be confused by the fact that mass and energy, because of their special status, can vanish from the system only by going somewhere else. That is to be contrasted with things like enthalpy or entropy content, or color and smell, which can simply vanish from the universe entirely.

Answer 6

Insulate the system.Remove all external connections.The system becomes isolated.