Physical and Chemical Properties of Water
Physical
Water is the most cohesive non-metallic liquid. Hydrogen has a positive charge and Oxygen has a negative charge, so they attract each other and form a bond. Capillary action happens because of waters cohesiveness and stickiness. Capillary action occurs when the adhesion of water to the sides of the vessel it is in are stronger than the forces between the molecules. Another physical property of water is its color, water is actually not colorless, despite popular belief, but is actually slightly blue tinted. Waters color comes from its molecules absorbing the red end of the spectrum of light.
Chemical
Water acts as an insulator when it dissolves substances. If water holds a large amount of solutes
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The hydrogen and oxygen atoms share electrons, but the oxygen has more of the electrons than the hydrogens. Oxygen has more electrons, so it has a slightly negative charge, and hydrogen has less electrons, so it has slightly positive charge.
Water Molecules Geometric Shape and its Effects on Water Properties
Waters hydrogen and oxygen bond is on an angle of 104.5o, so the molecule is bent. The bent geometric shape and the increase of electrons on the oxygen side and the lack of electrons of the hydrogen side make water have very unique properties.
Water is a Universal Solvent
Water can dissolve more substances than any other liquid, which is why it is known as the universal solvent. Water is the universal solvent because of its physical and chemical properties. The polarity of a water molecule, one side being positive and the other being negative, allows many different molecules to attract to either the positive or negative side. The strong attraction makes water a great solvent.
The High Boiling Point of Water in its Molecular
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The intermolecular forces between water molecules cause surface tension. Molecules on the surface of a liquid are attracted to the molecules inside and to each other. Molecules inside the liquid have no force of attraction because other molecules surround them.
Water’s Phase Change and the Specific Properties of Each Phase
Water has the very unique physical property of being the only natural substance found as a solid, liquid, or gas. To change water from one phase to another you must have a great amount of energy. Water at or below 0oC is a solid (ice). Water at 0oC or above is a liquid. Water at 100oC is a gas (water vapor).
Gas
Water vapor is compressible, expandable, and takes up a lot more space than the other phases. It is free moving and has no definite shape or volume.
Liquid
Liquid water is not as easily expanded as gases. It will take the shape of the container it is put in and the motion of the particles is more restricted than those in gases, but less than those in solids.
Solid
Solid water is hard and less dense than its liquid form, which is rare. The particles do not change shape or expand/contract with the container it is put
When in solution, the hydronium and chloride ions formed will be partially surrounded by water molecules via ion-dipole bonds, an electrostatic force of attraction that exists between charges in the ions and the partial charges in the water molecules. Water molecules surrounding ions is called hydration.
At a constant temperature, a pure liquid has a vapor pressure that describes the pressure of escaped gaseous molecules that exist in equilibrium at the liquid’s surface. Adding energy to a pure liquid gives more molecules the kinetic energy to break the intermolecular forces maintaining the liquid and raises the overall temperature of the liquid. Eventually, adding energy boosts the liquid’s vapor pressure until it equals the surrounding atmospheric pressure. When this occurs, the pure liquid boils at a temperature called the boiling point.
Matter exists in three basic states: solid, liquid, or gas. A substance experiences a phase change when the physical characteristics of that substance change from one state to another state. Perhaps the most recognizable examples of phase changes are those changes from a solid to a liquid or a liquid to a gas. When a substance goes through a phase change, there is a change in the internal energy of the substance but not the temperature of the substance (Serway, et al. 611).
The reason why the gummy bear expanded and swelled in water is because of diffusion and going through osmosis. The molecules did diffusion by going from high concentration (the water) to the low concentration (the gummy bear). The diffusion of the water molecules went through a selectively permeable membrane to perform osmosis. By performing diffusion and osmosis, the molecules were at an equilibrium, which is when the concentration of molecules are equal on either side of the selectively permeable membrane. Although the membrane lets certain molecules through, some larger molecules cannot pass which is how basic living things perform life processes such as transporting water in a
Surface tension effects in wet particle assemblies cause the Liquid bridge forces. When the particle diameter is 1 mm, then these forces become dominant.
...nstead of the common crystalline state, something that is extremely hard (gizmodo.com). That’s where the liquid levitation comes in, a machine that uses sound waves to make liquid solutions float. This way the liquid solutions don't touch any solid materials as the water evaporates, solidifying in the much desired amorphous drug, so it can be more efficient in helping.
The Biological Importance of Water as a Solvent and as a Medium for Living Organisms
Water is the most important molecule that exists on the Earth. Without water living beings would not be able to live. Water is used for an immeasurable number of things. There are many properties of water, which makes this molecule so unique. One which people overlook is hardness. Hardness is defined in the Chemistry: The Central Science by Prentice Hall's as being "water that contains a relatively high concentration of Ca2+, Mg2+, and other divalent cations." Water containing these ions is not a health hazard; however, it is a problem for industries and households. Therefore, the hardness of water is vital to understand in order to prevent the problems it could cause.
Gases take one form of physical appearance for substances. By definition, a gas represents a grouping of molecules at a high energy such that the volume it occupies is determined by container, and can be molded and compressed into smaller packages via reduction of energy. Manipulating energy is the gases results into a change in form and physical appearance, which engages various phases from solid, liquid and gas. In the gaseous form the pressure (P), volume (V), absolute temperature of the gas (T), molar gas constant (R) and the number of moles (n) are the factors that can be manipulated to derive various characteristics of the gas to establish a relationship between the characteristic of the gas (Castka, Metcalfe, Davis, & Williams, 2002).
Introduction: A phase change is a result from the kinetic energy (heat) either decreasing or increasing to change the state of matter (i.e. water, liquid, or gas.) Thus saying, freezing is the phase change from a liquid to a solid which results from less kinetic energy/heat. Also, melting is the phase change from a solid to a liquid which results from adding kinetic energy/heat. So, the freezing and melting point of something is the temperature at which these phase changes occur. Therefore, a phase change will occur when a vial of 10 mL of water is placed into a cup of crushed ice mixed with four spoonfuls with 5 mL of sodium chloride for 30 minutes. If 10 mL of water is placed in an ice bath, it will then freeze at 5 degrees Celsius because the kinetic energy will leave quicker with the ice involved. The purpose of this lab is to observe what temperature the water must be to undergo a phase change.
The same was true for diffusion in a liquid. The cold water diffused at a much slower rate than the room temperature water did. Though the gel and liquid are two different states of matter, the experiments both help solidify how diffusion works in different temperature settings.
Carbon dioxide is commonly found as a gas and is never a liquid. It sublimes to a solid known as 'dry ice' which is used as a substitute for normal ice as it is a lot colder and doesn't melt.
Each water molecule consists of one oxygen atom and two hydrogen atoms. The oxygen atom (or the apex of the water molecule) bears a slight electronegative charge while hydrogen possesses a more positive one. Because opposite charges attract, the water molecules are drawn together. When an oxygen atom is linked to a neighboring molecule's hydrogen atom, a bond called a hydrogen bond is formed. In an ice crystal the hydrogen bonds to give the shape of the crystal so that the grid of molecules surrounds relatively to large spaces. In a liquid form, water has no such spaces; so ice is less dense and will float on liquid water. If not for this, great bodies of water would freeze from the bottom up without the insulation of a top layer of ice and all life in the water would die.
First of all, the purpose of this lab was to determine the water’s vapor pressure at different temperatures as well as to measure the molar heat of vaporization of water using the Clausias Clapeyron equation. The first concept out of many represented in this lab is the ideal gas law. The ideal gas law is used to get the number of moles of air trapped in the 10 mL graduated cylinder. Once we cooled the system so that water vapor is extremely minute, and then we determined the number of moles of air using the ideal gas law. The number of moles of air equals to the pressure (in atm) times volume divided by constant times temperature. One would assume that when the water is heated to 80 degrees, the number of air molecules in the air bubble would decrease, but it actually stays constant. This is due to the fact that there is no air coming in or out of the cylinder. As the temperature gets closer to 80 degrees, the number of air molecules stays the same but the water vapor increases. And the bubble expands to keep the pressure at the same level. The ideal gas law was also used when the partial pressure of air in the gas mixture is calculated. This is gotten from number of moles multiplied by the constant and the constant and the whole thing divided by the volume.
6. When water is distilled, it does not vaporize all at once when the boiling point is reached. When some water molecules evaporate, the kinetic energy of the remaining liquid goes down and the temperature drops slightly. As a result, the rest of the water needs to be heated again before more molecules of water evaporate. A constant source of heat is needed.