These problems are exactly like mixing two amounts of water, with one small exception: the specific heat values on the two sides of the equation will be different. The water specific heat will remain at 4.184, but the value for the metal will be different.
a) The colder water will warm up (heat energy "flows" in to it). The warmer metal will cool down (heat energy "flows" out of it). b) The whole mixture will wind up at the SAMEtemperature. This is very, very important. c) The energy which "flowed" out (of the warmer water) equals the energy which "flowed" in (to the colder water)
Please note the starting temperature of the metal is above the boiling point of water. In reality, the sample may vaporize a tiny amount of water, but we will assume it does not for the purposes of the calculation. Solution:
Solution: 1) The basic equation to be used is this: Heat gained or lost = (mass) (temperature change) (specific heat) In more compact form: q = (m) (Δt) (Cp) There will be three of them used below. 2) The two masses associated with the gold and the silver rings: Let y = grams gold Therefore, 15.0 − y = grams silver 3) The mass of water:
Over time the metal will cool and the water will heat up. Eventually the two objects will have the same temperature. They are then said to be in thermal equilibrium with one another. During the intervening time the hot metal is transfering energy to the water.
So hot water is less dense than cold water. When you put the two together with the hot water on the bottom, the hot water rises to the top, mixing with the cold water along the way and creating purple water.
Because the hot water will heat the cold water up and the cold water will cool the hot water down until they have the same temperature. There is more energy in the hot water than the cold water. When the hot & cold water mix, the energy evens out so the temperature will be averaged.
As the temperature of the water in the beaker increases, both the energy and speed of the molecules increases. As the water molecules absorb heat energy they move faster. Heat is conducted to the water molecules by collisions with faster moving particles.
When water is cooled, the water molecules move slower and get closer together. This makes cold water more dense than room temperature water. Since cold water is more dense, it sinks in the room temperature water. When water is heated, the water molecules move faster and spread out more.
When fluids are cooled, they contract and therefore become more dense. Any object or substance that is more dense than a fluid will sink in that fluid, so cold water sinks in warmer water. Hot air rises and cold air descends for exactly the same reason.
When hot liquid is mixed with cold liquid, the molecules collide and transfer heat. When heat is transferred, the temperature is undefined. Once the heat energy is shared by the molecules, the system reaches equilibrium and the temperature becomes nearly constant.
When two cups of cold water of the same temperature are mixed, the water will be twice as cold. Thermometers are used for measuring heat. The temperature of iced water at 0 °C will go down when more ice is added.
When two liquids at different temperatures are mixed and the resultant temperature is found to be the mean of their temperatures then their densities must be equal.
During heating process the water at base gets the heated first so temperature at bottom is more therefore density is less and hence moves upward.
Convection is the transfer of thermal energy from one place to another by the movement of gas or liquid particles. How does this happen? As a gas or liquid is heated, the substance expands. This is because the particles in liquids and gases gain kinetic energy when they are heated and start to move faster.
Beakers and Erlenmeyer flasks can be heated directly on a hot plate. These containers have a flat bottom and heat will be spread evenly throughout the solution when the solution is also stirred. Other containers that do not have a flat surface should be heated indirectly.