Melting IceI picked this topic for a couple of reasons, which I will give you in this opening paragraph. My first reason is that it is simple and educational. Also, it has given me new knowledge about molecules and matter. Secondly, I think melting ice, which is a solid turning into a liquid, is cool. Lastly, I just love to do science experiments.
Water exists in three distinct forms or phases: solid ice, liquid water, and gaseous steam (Fig 15.1.1).
These phases differ in how easily their shapes and volumes can be changed. Solid ice is rigid and incompressible, preventing you from altering an ice cubes shape or volume. Liquid water is a compressible fluid. You can reshape a water drop, but can not change its volume. Gaseous steam is a compressible fluid. You can vary both the shape and volume of the steam in a tea kettle.
These different characteristics reflect the different microscopic structures of steam, water, and ice. Steam is a gas, a collection of independent molecules that is also called water vapor. These water molecules bounce around their container, periodically colliding with one another or with the walls. The water molecules fill the container uniformly and easily accommodate tiny changes in its shape or size. Enlarging the container decreases the steam’s density and lowers its pressure. To be independent of one another, the water molecules in steam need a certain amount of thermal energy. Without this energy they stick together to form water.
Water is a liquid, a disorderly fluid collection of molecules, that is held together by chemical bonds. These bonds pack the molecules tightly together and give water its fixed volume. However, water still has enough thermal energy for its individual molecules to separate briefly and form new bonds with different partners. Its evolving microscopic structure makes water fluid. While its volume is fixed, its shape is not.
When the water molecules have even less thermal energy, they are unable to rearrange and cling together stiffly as ice. Ice is a solid, a rigid collection of chemically bound molecules. Like most solids, ice is crystalline, with orderly arrangements of molecules that extend over large distances. This order produces the beautiful crystalline facets of snowflakes and frost. Just as an orderly arrangement of cannon balls takes up less volume than a disorderly one, a crystalline solid usually occupies less volume than its corresponding liquid. That’s why the solid phase of a typical substance sinks in the liquid phase of that same substance. There is an exception to that rule.
Water, ice’s crystalline structure, is unusually open and its density is surprisingly low. Almost unique in nature, solid ice is slightly less dense than liquid water, so that ice floats on water. That is why icebergs float on the open ocean and ice cubes float in your drink. In fact, water reaches its greatest density at about 5 degrees Celsius, 40 degrees Fahrenheit . Heated above that temperature, water behaves normally and expands.
However, water also expands as you cool it below that temperature, a very unusual effect. Melting ice and freezing when you heat ice, it remains solid until its rising temp hits zero degrees centigrade. At that point, the ice stops getting warmer and begins to melt.
At that point the ice stops getting warmer and begins to melt. Melting is a transition, a transformation from the ordered solid phase to the disordered liquid phase. This occurs when heat breaks some of the chemical bonds between water molecules and permits the molecules to move about.
The ice transforms into water, losing its rigid shape and crystalline structure. Zero degrees celsius is ice’s melting temperature. http://www.howeverythingworks.
org/supplements/water_steam_and_ice.pdf/This next paragraph will be about the effects of salt on ice. Salt lowers the melting point and the freezing point of ice.
Ice forms when water becomes zero degrees celsius. When salt is added to ice it dissolves into liquid water within the ice and lowers the temperature and freezing point. “A 10% salt solution freezes at -6 degrees Celsius, and a 20% salt solution freezes at -16 degrees celsius.” If anybody has ever watched salt melting ice, you can see the dissolving process happen as the salt dissolves into the water and spreads out from the point first melted. Although, if the temperature of the roadway is lower than -9 Celsius or so, then the salt really won’t have any effect on the solid. Salt cannot get into the structure of the solid water to start the dissolving process. I’m very excited about doing the salt experiment. https://whatmakesicemeltfastest.
weebly.com/ Solids are easy to describe – they are solid! The molecules in a solid are crammed close together in regular structures. They do not have enough energy to break free of the attraction that holds them in.
You cannot pass through a table because both you and the table are solid. Solids have the least amount of energy of the three traditional states of matter. The particles are arranged into a regular pattern with very little space between the particles. The particles are held together by strong forces and can only vibrate around a fixed position. Due to this, solids have high density and a fixed shape and volume. If you leave a table for a few days, it doesn’t spread into a thin layer of wood across the floor or expand to fill your living room! (Wingate, Philippa. “Essential Physics.
” Essential Physics, Usborne Pub., 1992, p. 30.) Just like solids, the particles in liquids are packed closely together, although in a more jumbled-up random way.
Unlike solids, however, we can pass through liquids. This is due to there being fewer and slightly weaker forces between the particles. The particles can move around each other and solids can be forced between liquid particles. Liquids also have a fixed volume but not a fixed shape.
Liquids will flow to take up the shape of the bottom of the container. All liquids can flow, but some liquids are runnier than others. The thicker a liquid is, the stronger the forces between its particles. For example, syrup has stronger forces between its particles than lemon juice. Liquids have more kinetic energy than solids, but much less than gases. The particles in gases are far apart and randomly arranged.
This state of matter has the highest kinetic energy of the three traditional states of matter. There are almost no forces between the particles. The particles are constantly moving in all directions, bashing into each other and the sides of their container. Gases also flow to completely fill their container, regardless of its size or shape. Gases have no fixed shape or volume. https://owlcation.
com/stem/what-is-the-particle-model/ We experience water and it makes up 60% of the human body. What do we know about this most essential of molecules? Water is made up of two hydrogen atoms and one oxygen atom (H20). Each hydrogen atom forms a bond two the central oxygen atom (H-O-H). The hydrogen atom has one electron, whereas oxygen has eight, so the oxygen atom is much larger than the hydrogen. The water molecules look a little like Mickey Mouse because the atoms are at 140 degree angle to each other.
http://www.open.edu/openlearn/science-maths-technology/science/chemistry/how-molecules-interact-h2o/ London Scientist henry Cavendish (1731-1810) discovered hydrogen and reported that it produced water when reacted with oxygen. Antoine Lavoisier (1743-1794) later reproduced Cavendish’s experiment and gave hydrogen its name. Due, perhaps to the erroneously perceived simplicity of water, little further investigative work on water was attempted during the rest of the 18th and 19th centuries.