Chemistry · Ch 4 — Chemical Thermodynamics
Types of system
Types of system
Three types of systems are shown in Fig. 4.2.
Drawn by us to help you understand the concept clearly, and verified to make sure it's accurate. For exams, practice from your textbook's own diagram.
What this figure shows. Three cartoon sketches side by side. (a) Open system — an open cup of steaming coffee on a saucer, with arrows labelled Matter (the escaping vapour) and Energy (the heat released): both are exchanged. (b) Closed system — the cup covered with a saucer; arrows labelled Energy pass through, while the Matter arrow is blocked: energy is exchanged, matter is not. (c) Isolated system — the cup inside a box whose hatched walls are labelled …
i. Open system : Fig. 4.2(a) shows an open cup containing hot coffee placed in a room. You observe that the coffee cools down, releasing heat to the surroundings; the water vapour from the coffee simultaneously passes into the surroundings. Such a system (the coffee), which exchanges both energy and matter with the surroundings, is called an open system.
ii. Closed system : In Fig. 4.2(b), a cup containing hot coffee is covered with a saucer. The coffee cools down by giving away heat to the surroundings, but the water vapour from the coffee now does not pass into the surroundings. Such a system, which exchanges energy and not matter with the surroundings, is called a closed system. …