Problem 1 (II) (a) An ice cube of mass m at 0°C is placed in a large 20°C room. Heat flows (from the room to the ice cube) such that the ice cube melts and the liquid water warms to 20°C. The room is so large that its temperature remains nearly 20°C at all times. Calculate the change in entropy for the (water + room) system due to this process. Will this process occur naturally? (b) A mass m of liquid water at 20°C is placed in a large 20°C room. Heat flows (from the water to the room) such that the liquid water cools to 0°C and then freezes into a 0°C ice cube. The room is so large that its temperature remains 20°C at all times. Calculate the change in entropy for the (water + room) system due to this process. Will this process occur naturally?

Consider a 50.0 g ice cube placed in a container containing 200 g of water. The water is initially at 25.0*C and the ice cube comes directly from a freezer at -15.0*C. Assume no heat is lost to the surroundings and negligible heat loss from the container. Determine the total change in entropy as a result of the mixing process.

A heat engine that operates between two heat reservoirs at 900 ° C and 0 ° C, respectively, it has an efficiency of 35% and receives 21 kJ. If the tank temperature low is the environment, determine its entropy variation. a) -50 J / K b) 296.7 J / K c) 50 J / K d) ∞

Suppose you put a cube of ice of mass 100 g into a glass of water at just above 0°C. When the ice melts, about 33 kJ of energy is absorbed from the surroundings as heat. What is the change in entropy of (a) the sample (the ice) and (b) the surroundings (the glass of water)?