What is Ice: Definition and 980 Discussions

Ice is water frozen into a solid state. Depending on the presence of impurities such as particles of soil or bubbles of air, it can appear transparent or a more or less opaque bluish-white color.
In the Solar System, ice is abundant and occurs naturally from as close to the Sun as Mercury to as far away as the Oort cloud objects. Beyond the Solar System, it occurs as interstellar ice. It is abundant on Earth's surface – particularly in the polar regions and above the snow line – and, as a common form of precipitation and deposition, plays a key role in Earth's water cycle and climate. It falls as snowflakes and hail or occurs as frost, icicles or ice spikes and aggregates from snow as glaciers and ice sheets.
Ice exhibits at least eighteen phases (packing geometries), depending on temperature and pressure. When water is cooled rapidly (quenching), up to three types of amorphous ice can form depending on its history of pressure and temperature. When cooled slowly, correlated proton tunneling occurs below −253.15 °C (20 K, −423.67 °F) giving rise to macroscopic quantum phenomena. Virtually all ice on Earth's surface and in its atmosphere is of a hexagonal crystalline structure denoted as ice Ih (spoken as "ice one h") with minute traces of cubic ice, denoted as ice Ic and, more recently found, Ice VII inclusions in diamonds. The most common phase transition to ice Ih occurs when liquid water is cooled below 0 °C (273.15 K, 32 °F) at standard atmospheric pressure. It may also be deposited directly by water vapor, as happens in the formation of frost. The transition from ice to water is melting and from ice directly to water vapor is sublimation.
Ice is used in a variety of ways, including for cooling, for winter sports, and ice sculpting.

View More On Wikipedia.org
Recent contents Top users
  1. H

    Thermodynamics: Why does salt lower the melting point of ice?

    There was a question on "Why salt lower the freezing point of water?"I found the following answer."Thermodynamics teaches that a loss of entropy can be overcome by a gain in so called enthalpy". The loss of entropy by freezing the solution canbe over come at temperature much below 0 degree C...
  2. H

    Ice Ages & Tilting Earth: Separating Fact from Fiction

    I came across an article regarding a study that claimed ice ages correspond with extreme changes in the tilt of the Earth. I'm curious what others think about this. Is this just another unqualified scientific study put out there to confuse the climate change debate? Is the science behind it...
  3. A

    Volume of ice needed to mitigate ocean warming since 1871

    According to following study 436 x 10^21 J of energy have been absorbed by the Earth's oceans since 1871. https://www.pnas.org/content/116/4/1126 What thickness of ice covering the globe would be needed to melt in order to absorb this amount of energy, assuming that all energy goes towards the...
  4. Mimosapudica

    Power developed by a person on eating 100g of ice per minute is?

    P=W/t W=Q= mL = (100x 80x 4.2)/1000 (kg x J/kg) = 33.6 t= 1 minute= 60s P= 33.6/60= 0.56 watt... but the answer provided is 560J/s...?
  5. A

    Work and energy of an object on a ice slope

    Homework Statement: A perfect hemisphere of frictionless ice has radius R=7 meters. Sitting on the top of the ice, motionless, is a box of mass m=7 kg. The box starts to slide to the right, down the sloping surface of the ice. After it has moved by an angle 11 degrees from the top, how much...
  6. M

    Find the fractional increase in inertial mass when an ice cube melts

    Summary: Apparently an ice cube gains mass when it melts So I'm asked to "Find the fractional increase in inertial mass when an ice cube melts ". All I've got off the top of my head right now is that a cube has energy = mc^2, and then when the cube melts, energy Q = (Heat of fusion)(m) is...
  7. L

    Dry ice -- How do the stores keep it from evaporating?

    Ok, how do stores keep dry ice from sublimation(i think i spelled that correctly) or evaporating? Are the coolers at my local walmart some sort of special type of mechanism? thanks
  8. C

    I Transporting an Ice Cream Tub in hot weather

    It was hot and I bought a tub of ice cream to take home. I put the AC on and blew into the footwell where the ice cream was. Was that sensible? Is it better to let a static layer of cold air surround the tub of ice cream (say at -5C), or to blow cold (~+10C) air over it when the ambient in...
  9. L

    Are the Fats in Chocolate Bars Healthier Than Those in Ice Cream?

    They say not to eat so much ice creams because there are so many fats in it. Fats are required to produce the ice cream texture. How about fats in chocolate bars like Hersheys? Are they the same fats or the ones in the chocolates are better for health?
  10. G

    Why does 32 F ice have more energy than 32 F water?

    Why does 32 F ice have more energy that 32 F water?
  11. D

    Clear Ice industrial generation issues

    Summary: Problems generating industrial clear Ice tube. The ice is cracking and we don't know why. Summary: Problems generating industrial clear Ice tube. The ice is cracking and we don't know why. Hi all! I'm an engineer from Spain and I'm working in a new project (factory ice). We have...
  12. N

    Question about using the ICE table

    This is how I started my ICE table: $$CO(g)$$ $$H_2O(g)$$ $$H_2(g)$$ $$CO_2(g)$$ Initial (mol) 0.40 1.00 0 0 Change (mol) -0.40α -1.00α 1.4α 1.4α Equilibrium (mol) 0.40-0.40α 1.00-1.00α 1.4α 1.4α (or should I use 0.225) I am not sure if my table is correct. When I work out the total...
  13. W

    B How Can You Model a Man Sliding on Rough Ice with Intermittent Pushing?

    How would you model the following situation? A man of mass m slides on rough ice with coefficient of kinetic friction ##\mu_k##, while pushing outwards at intervals to try to come to a stop in a shorter time. For example, he might slide for 5 seconds then push out with his right foot, then...
  14. C

    Comparing Water and Ice Melting for fighting fires

    Good morning, I'm wondering on this question for a while. Imagine we have a fire progressing in a corridor 30 meters wide at a known velocity. What kind of barrier (of the following) can be most successful in minimizing or even erasing this fire and why: a water-soaked area, or a zone covered...
  15. P

    Ice Skating conservation of momentum (conceptual problem)

    Homework Statement Two ice skaters have masses m1 and m2 and are initially stationary. Their skates are identical. They push against one another, as in Figure 7.11, and move in opposite directions with different speeds. While they are pushing against each other, any kinetic frictional forces...
  16. brotherbobby

    Solving Rotating Ice Skaters Problem: Is their Straight Line Parallel?

    Statement of the problem : Two ice skaters circle about a point while holding hands. At a certain moment both let go and move along straight lines. Are the two straight lines parallel? Explain. My attempt : Calling the two ice skaters ##S_1## and ##S_2 ##, they must lie...
  17. CrosisBH

    Mass of Ice required to achieve a certain final Temperature

    Homework Statement An insulated beaker with negligible mass contains a mass of 0.350 kg of water at a temperature of 76.5 °C. How many kilograms of ice at a temperature of − 23.9 ∘C must be dropped in the water to make the final temperature of the system 40.0 ∘C? Take the specific heat for...
  18. J

    I Ice patterns on the inside of my windshield

    I got into my car last night saw these patterns on the inside. Some of them just look like frost formed on some streaks from when I must have wiped it, but then there all these really intricate patterns of intersecting straight lines. There were no cracks or scratches on the interior that I...
  19. C

    Global Ice melt and heat balance

    Can anyone point to a refereed paper exploring the heat absorbed by melting around 500 GT of ie per year (Antarctic - 127 GT pa; Greenland 286 GT pa; sea ice, glaciers estim. 100 GT pa)? As latent heat of fusion is 333.55 KJoules per Kg, I reckon the heat absorbed per year is around 1.67 X 1023...
  20. jtbell

    Did a Massive Ice Disk Really Form in Maine's Presumpscot River?

    A giant ice disk, almost perfectly circular, has formed in the Presumpscot River in Westbrook, Maine: https://www.npr.org/2019/01/16/685816019/a-massive-moving-ice-disk-takes-center-stage-mesmerizing-maine As it slowly rotated, contact with one shore smoothed away the irregularities at its edge.
  21. P

    How will melted ice in a pool change the water level

    if I have a pool that is 20x20 surface area and I put a 200 gallon block of ice it, the water level will go up by X amount. when it melts how much will the water level change?
  22. M

    Heat Energy and Power -- Heating ice in a copper pan

    Homework Statement Calculate the power needed to heat a 1360 gram chunk of ice in a 600 gram copper pan from 0 ◦C to the system’s final temperature of 35◦C in a time of 10 minutes. Homework Equations Q=mcchange in temp Q=mLf P= energy/time The Attempt at a Solution I thought that adding the...
  23. L

    Simple Ice Skater with Conservation of Angular Momentum

    Homework Statement Not a HW problem, but a "me re-thinking things" problem. Please tell me where my thinking is flawed: You have an ice skater with no net external torques acting on him/her. (We are analyzing the time after they have to get an external torque on them by pushing off of the...
  24. jedishrfu

    B Breaking Down the Mystery of Ice VII Nucleation

    A new form of ice has been discovered dubbed ice VII: https://arstechnica.com/science/2018/10/weird-water-phase-ice-vii-can-grow-as-fast-as-1000-miles-per-hour/ https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.121.155701
  25. S

    Calculate Work and Entropy Change for an Ice Maker

    <edit: moved to homework. No template in the post.> An ice maker inputs liquid water at 25 degrees C and outputs ice at -5 degrees C. Assume there is 1 kg of water and the volume does not change. Cp liquid 4.18 kJ/kg-K Cp solid 2.11 kJ/kg-K ∆H fusion 334 kJ/kg I need to...
  26. A

    Find Her Acceleration (2 ice skaters pushing a 3rd skater)

    Homework Statement : [/B] It may be impossible to solve without the picture. Therefore, I linked the picture instead of typing the question. Link/picture of question: https://gyazo.com/124652a4718764aa0f7e8217c1d3fcbc I'm stuck on the third question. The third question is the following: "What...
  27. J

    Finding the acceleration of a block of ice on a ramp

    Homework Statement A a block of ice with mass mA rests on a wedge of ice with mass mB=4.33 kg that is cut so that the surface of the wedge makes an angle of θ=38.1° with the ground. There is no friction between the pieces of ice or between the ice and the ground. At time t=0, the blocks are...
  28. M

    Light wavelength transmission through ice

    I am studying hailstones. I have set up an experiment to pass colored light through hail, one color at a time for the colors of the visible spectrum, Red, Orange, Yellow, Green, Blue, Indigo and Violet (ROYGBIV). I have measured the dominate wavelength for each color with a photo spectrometer...
  29. S

    Ice Melts: Examining the ΔU, w and q of 0oC Water

    Homework Statement The first law of thermodynamics may be expressed in the form: ΔU = q + w, where ΔU is the increase in internal energy, q is the thermal energy supplied to the system, w is the work done on the system. Is ΔU, w and q positive, negative or zero when ice melts at 0oC to give...
  30. Gspace

    How Much Ice Can 10 Meters of Warm Water Melt in the Arctic?

    In the Arctic, if I had 10 vertical meters of 1 degree Celsius water above freezing brought to the surface, how much ice would that melt?
  31. C

    I The amount of time it will take to melt ice

    What information / formulas do I need to calculate / estimate the amount of time required to melt an ice cube of temperature $T_i$ and mass $m$ in $M$ kg of $T_w$ temperature water? Assume that the system is insulated. Is it even possible? I'm fine with Calculus.
  32. C

    Answer: Terminal Temperature of Water with Ice Cube

    We have a glass containing 0.5 liter (0.5 kg) of water whose temperature 100 degrees Celsius. We also have an ice cube with mass 0.01 kg and temperature -10 degrees Celsius. The cube is put into the glass. The glass is then insulated from the outside world, until the cube has melted. What will...
  33. L

    Piece of iron put into container with ice

    Homework Statement We put 1kg iron of temperature 100 Celsius into container with 1kg of ice, temperature 0 Celsius. What is state of the system after reaching equilibrium? Calculate change of entropy. Coefficient of melting of ice (c_L) is 330 kJ/kg, coefficient of heat transfer of iron (c_I)...
  34. Stephenk53

    B Running on Ice: My High School Story

    I am currently in high school and about to graduate, any way in the past I often threw caution to the wind and ran on ice when I walked home from school. When I was in middle school it went as poorly as one would expect but for some reason I kept trying, in early high school I became extremely...
  35. Nojins

    Conservation of Energy with changing masses on ice

    Homework Statement Mass 1(75kg) glides on ice at 1.8 m/s to a second stationary mass, (52 kg) How far will the pair slide after the collision if the coefficient of kinetic friction between the ice and their skates is .042? Homework Equations Conservation of energy, Kinetic Energy, Work...
  36. C

    B Interplanetary travel, Arctic sea ice

    I'm a software developer, no formal astro-physics education, but would like to pose some questions/hypotheticals regarding interplanetary travel, and/or dynamic positioning of Earth orbiting objects using extraterrestrial fuel sources. 1. Asteroid-based hitch-hiking to other planets...
  37. Juicer82w

    B Launching a Juice Company: Seeking Advice on Slush-Ice Production

    Hi, I'm a student who's creating a project surrounding the start-up of a juice company. We currently experiment with juice slush-ice but we don't know how to make it, neither do we know if it's possible. I would really appreciate if anyone at this site knows anything about this subject, and the...
  38. Juicer82w

    Exploring the Possibilities of Juice Slush-Ice: A Student's Project

    Hi, I'm a student who's creating a project surrounding the start-up of a juice company. We currently experiment with juice slush-ice but we don't know how to make it, neither do we know if it's possible. I would really appreciate if anyone at this site knows anything about this subject, and the...
  39. Humbleness

    Heat transfer, how long it takes ice to reach melting point

    Homework Statement A 0.25 kg piece of ice at -30 C is warmed by an electric heater and the following graph of temperature is produced. Assume that there has been no loss of energy to the surroundings. - Use the info on the graph to determine the power output of the heater - Explain how long...
  40. karush

    MHB Ice Skating Collision: Daniel & Rebecca

    8.27 Two ice skaters Daniel (mass 65.0\text{ kg}) and Rebecca (mass 45.0\text{ kg}) are practicing. Daniel stops to tie his shoelace and, while at rest, is struck by Rebecca, who is moving at 14.0\text{ m/s} before she collides with him. After the collision, Rebecca has an initial direction...
  41. T

    Unit Vectors and Momentum Changes in a Block of Ice

    Homework Statement A 0.5 kg block of ice is sliding by you on a very slippery floor at 2.5 m/s. As it goes by, you give it a kick perpendicular to its path. Your foot is in contact with the ice block for 0.0035 seconds. The block eventually slides at an angle of 24 degrees from its original...
  42. I

    Help, Ice racing tire - which one will destroy ice faster?

    I have attached four Ice racing tires commonly used on cars and trucks. One of these is my own personal design that I have been racing with for a couple years now and still in the R/D stage but everyone keeps telling me my tire will destroy the ice we race on (think oval track) too fast and I...
  43. I like Serena

    How can we melt ice in a microwave efficiently?

    I've noticed that when I put a prefab meal in the microwave, the parts that are frozen over just don't defrost any time soon, even though the rest of the meal gets really hot. The reason is that the ice structure doesn't allow the polar water molecules to vibrate. My question: what can we do so...
  44. C

    Thermal physics -- Latent heat melting ice

    Homework Statement Question (b) (iii) Homework EquationsThe Attempt at a Solution The energy required to melt the ice is Q1=mL=3*0.025*3.3*10^5=24750J The energy released by water is Q2=mcT=0.33*4200*(22-T) Shall I calculate the energy that the ice needs after it melts into water? i.e...
  45. Wrichik Basu

    B Why are only some parts of this ice block cloudy?

    I had a sprain in my leg a few days back. The doctor recommended dipping my foot alternately in ice-cold and hot water to aid blood circulation. It is here that I discovered something interesting. The picture above shows the piece of ice that was put in the bucket. The above picture shows...
  46. Noisy Rhysling

    Energy requirement for melting through five klicks of ice?

    Related to exploration of Europa: If we elect to send a probe to bore through (guessimate) five kilometers of ice to reach the Covered Seas, and have a diameter of 100 mm and length of one meter, how much energy will the probe require to reach unfrozen areas? AND given that figure, is it...
  47. C

    Thermodynamics Ice Melting Question

    Homework Statement On a hot summer day, you planned a trip to a beach, but you inadvertently took a wrong turn and now you’re worried the ice in your cooler is going to melt. The cooler is 0.5 m × 0.5 m × 0.4 m, and is made with 5 cm thick Styrofoam (k = 0.033 W/m2K). Help your panicking...
  48. starstruck_

    Why does water level stay the same when ice melts inside the water?

    I feel so stupid, intuitively, when we were having this discussion I wanted to say that the level stays the same but when we were discussing with the person beside us, my partner said it would fall because water expands when it freezes, so when it melts, there'll be less displacement, so the...
  49. nmsurobert

    Build Comets in Classroom using Dry Ice and Blow Dryer

    i wasnt sure where to post this question. I want to build "comets" in my class room using dry ice. I am sure a few of you have seen this demo before. however, i want to use a blow dryer to warm it and to also create a stream of air so we can see the "tail" of the comet. I am also hoping that...
  50. D

    Solving Heat Transfer Problem with Melting Ice Cube

    Good day members of physics forums . I am a university student currently studying thermodynamics and I just am a bit confused about a heat transfer problem. If you have the following items: 1 metal container which is well insulated from the outside ; ; 1 quantity of water and an icecube ...
Back
Top