Does melting ice cause liquid to cool, and why?

Question

what about in terms of kinetic energy, potentional energy and the law of conservation of energy???

Answer 1

Yes,

According to the laws of thermodynamics the heat required to melt the ice has to come from somewhere. In this case the heat from the liquid is transmitted to the ice causing it to melt. (liquids are warmer than solids). This is the classic case of entropy (http://en.wikipedia.org/wiki/Entropy) this action represents the conservation of entropy, or the conversation of energy.

Entropy is the dispersal of energy that is lost from a system. Friction is a classic example; as an object moves it has to overcome the force of friction, thus requiring more energy. This extra energy is lost as heat, and the item that you are moving something over or through absorbs this heat. Due to entropy it spreads the heat out through the entire system and from there to the entire universe.

When something is warmer than absolute zero then the molecules inside it are vibrating; which is kinetic energy. The faster the molecules vibrate the warmer the object is. All substances have a point where the vibration becomes fast enough that they turn into liquids, then gases, then plasma. As an object cools, the kinetic energy is lost from those vibrating molecules and dispersed throughout the universe.

According to Wikipedia: http://en.wikipedia.org/wiki/Law_of_thermodynamics#First_law
According to the first law of thermodynamics: “Energy cannot be created or destroyed; rather, the amount of energy lost in a process cannot be greater than the amount of energy gained.” There is your conservation of energy.

According to the second law of thermodynamics: “There is no process that, operating in a cycle, produces no other effect than the subtraction of a positive amount of heat from a reservoir and the production of an equal amount of work” So the heat from the liquid is transferred to the ice and it does work by melting that ice (raising it’s temperature).

According to the third law of theermodynamics: “As temperature approaches absolute zero, the entropy of a system approaches a constant.” Another words the energy spreads out until eventually it is even throughout the entire universe somewhere above the temperature of absolute zero. Since no system is perfect we are always losing energy from it to entropy; which is then spread throughout the universe.

There are two theories of what happens next.

--In the Osculating Universe theory the black holes absorb all the energy of the universe along with all the matter then they absorb each other creating a super-super-massive black hole. This black hole cannot sustain itself so it explodes resulting in the big bang.

--In the Steady State Theory the energy dispersion caused by entropy spreads out across the entire universe and it then dies. For this theory to work black holes would have to have a limit to the amount that they can absorb and either explode or just disappear. I don’t know of any existing theory that can explain this limit. Recent discoveries have shown that at the heart of most galaxies (including ours; the Milky Way Galaxy) there is a super massive black hole. But, for some reason our super massive black hole and those in a few other galaxies are dormant right now. Can a black hole reach a point where it is full, and stops eating? Since it can happen then we might end up with a universe populated with dormant black holes and nothing else. Everything would have dispersed falling into the ultimate state determined by entropy.

Steven Hawking has flip-flopped on the idea, but then after he thought black holes existed he doubted they did exist until it was proven that they do exist. With the inclusion of black holes then it seems that the Osculating Universe is the most probably model, but we don’t know about Dark Energy or Dark Matter.

When astronomers try to measure the mass of the universe they come up short, in fact most of the universe is missing. Some of it could be hiding in black holes, we don’t know, but not all of it can, there simply hasn’t been enough time since the big bang for that to happen. The mass that the scientists couldn’t find was called dark matter (we can’t see it). The energy level of the universe is much less than it should be as well. Again some of it could be hidden inside black holes, but not enough. Scientists dub this as dark energy.

Dark Matter and Dark Energy have been just theoretical since Einstein’s day, but recently some astronomical work done seems to have found dark energy. It should obey the laws of energy and thermodynamics, as we know them, but what if it doesn’t? At that point something else could happen; thus allowing either the Steady State Universe or the Osculating Universe.

Back to your ice inside a liquid: The ice absorbs heat from the liquid, cooling the liquid. This absorption is the work that the ice does and it warms up the ice. Eventually you will have a liquid mixed with water where both are at the same temperature. If you leave the system alone then it will cool/warm to room temperature. When the sun dies then that diluted liquid would cool toward the temperature of space; which is around 4 degrees above absolute zero.

The energy is conserved, it is transferred as work, and then it is dispersed. This represents a loss of the kinetic motion of the molecules in the liquid, causing work to heat up the molecules in the ice. Since no system is perfect the rest of the heat is spent on the environment; thus bring your dilute liquid up to room temperature.

Energy is not lost it just spreads out.

Answer 2

The heat from the liquid transfers to the ice causing it to melt. Heat is considered to move into a cooler area and not the other way around because heat is nothing more than a form of energy. To view it the other way around you would imply that energy was being destroyed, which physics tells us is impossible.

To simplify, consider a glass of water with ice a closed system. The ice and water have a fixed amount of energy, some of which is heat. Heat will move against a gradient from areas of higher concentration to lower. The water has a higher concentration of heat than the ice so the heat moves from the water to the ice. This brings the ice to a temperature that causes it to change from a solid to a liquid (melting). Because the water has transfered some of it heat to the ice, the water has less heat energy, which typlically means a lower temperature.

Answer 3

yes, the ice would cause the liquid to cool. That is what ice is for. The heat energy travels from the liquid into the ice causing the liquid to cool down.

Answer 4

Yes, because the ice takes the heat of the liquid to melt, leaving it at a cooler temp.

Answer 5

because ice at melting point becomes water and it is still at a colder temperature than the liquid it is dissolving in, thus cooling the liquid. (or at least keeping it cool if it's already really cold)

Answer 6

Yes, because it would be taking in energy from the surrounding environment in order to change from solid to liquid.

Answer 7

This depends on what temperature the liquid is at the begin with.