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Wiki Assignment #9: Concentrated vs. Dilute and Strong vs Weak

1. The difference between a concentrated solution and a dilute solution is that a concentrated solution has a large amount of solute dissolved in the solution and a dilute solution has a small amount of solute dissolved and a large amount of solvent in the solution.

2. The difference between a strong vs weak acid solution is that a strong acid completely reacts with water and the forward reaction dominates. A weak acid does not react with water very much and the reverse reaction dominates.

3.

Wiki Assignment #8: Equilibrium 2

1. Once a chemical system has reached equililbrium, the concentrations of all reactants and products remain constant because the rate of change for each substance is equal so there is no loss or gain in concentrations of either reactant or product. An equilibrium is dynamic since the reaction is taking place, although the concentrations remain constant.

2. To write the equilibrium expression for a reaction, there must be a balanced chemical equation. The concentrations of the products, written in brackets, are written over the concentrations of the reactants, also written in brackets. To balance the equation, coefficients are used. CH4(g)+5O2(g)<=>CO(g)+6H2O(g) K=[CO][H2]3 [CH4]H2O]

3O2(g)<=>2O3(g) K=[O3]2 [O2]3

2C2H6(g)+7O2(g)<=>4CO2=6H2O(g) K=[CO2]4[H2O]6 [C2H6]2[O2]7

3. CO(g)=2H2O(g)<=>CH3OH(g) K=[CH3OH] [CO][H2]2

S(s)=3F2(g)<=>SF6(g) K=[SF6] [F2]3

Wiki Assignment #7: Equilibrium

One common example of equilibrium can be found in the game Tug of War. In this event, the two forces of pulling are equal and opposite, resulting in no visual change of the rope. [|Tug of War.doc] This image shows that the two forces, each having a force of 2.5 N result in no change. This example of equilibrium connects to chemical equilibrium which states that the forward chemical process proceeds at the same rate as their reverse reaction. Because the two reactions are equal, no net changes occur in the reactant. This is how the equilibrium system Tug of War and chemical equilibrium relate to one another.

Wiki Assignment #5: Investigating Solubility and Immiscibility

To clean up oil spills within a few hours of the occurance, booms are placed on the water which keep the oil from spreading out. Then the surface of the water is skimmed, using boats that suck or scoop the oil from the water into tanks. Another way to clean up oil spills is by using dispersants-chemicals that break down oil much quicker than it would alone. If an oil spill has reached a shore line, biological agents are used. Fertilizers are spread over the oil-slicked shoreline to foster the growth of microorganisms, which break down the oil. All of these techiniques help keep our environment safe of the damaging effects of oil, especially on our wildlife and oceanlife.

Solubility is the property of a solid, liquid, or gas chemical substance called solute to dissolve in a liquid solvent to form a homogeneous solution. The solubility of solids increases as the temperature of water increases. Gases become less soluble as temperature of water increases but more soluble in organic solvents. Stirring does not have an affect on solubility. Increasing the surface area of a substance has no affect on solubility. Rate of dissolution is a measure of how fast a substance dissolves. For liquid and solid solutes, increasing the temperature increases the rate of dissolution. For gases, an increase in temperature decreases rate of dissolution. Stirring increases the rate of dissolution because stirring increases the movement of the solvent which exposes solute to fresh solvent. Increasing the surface area also increases the rate of dissolution. When a solute dissolves, the action takes place only at the surface. When the total area of the solute is increased, the solute dissolves more rapidly.

__Wiki Assignment #4- Wonderful Water__ ===1) The boiling point of a substance is the temperature at which the liquid boils at a constant pressure. Water's boiling point is 100 degrees Celsius or 212 degrees Fahrenheit. Water has an unusually high boiling point because its bonds take more heat energy to overcome the bonds and change the liquid state to a gas. ===

[|Source #1][|Source #2]
===2) Surface tension is what causes the surface portion of a liquid to be attracted to another surface. Water at 20 degrees Celsius has a surface tension of 72.8 dynes/cm. Water has a high surface tension. === ===[|Source #1][|Source #2] === ===3) The density of a material is it's mass per unit volume. Water's density at 4 degrees Celsius is 1 g/ml or 62.4 lb/cu.ft. Water has a similar density compared to other molecules. === [|Source #1][|Source #2] ===4) A solvent is a solid, liquid, or gas that dissolves another solid, liquid, or gas creating a solution. Because many substances dissolve in it, water is a universal solvent. Not many substances are soluble unless they contain water. === [|Source #1] ===5) Molar mass of a substance is the mass of one molecule of that substance. The molar mass of water is 18.0153 g/mol. Water's molar mass is similar or average compared to other molecules' molar mass. ===

Boyle's Law states that at a constant temperature, as volume increases, pressure decreases because the gas particles do not collide with the sides of the container as often. This law also works backwards. As u squeeze a water bottle, you are increasing the pressure on the water bottle with your hand but decreasing the volume by squeezing the bottle.

Charles' Law states that at constant pressure, as temperature increases, volume also increases. This law also works backwards. In the summer the tires on your bike are completely pumped up with air. When you go to put your bike in the shed during the winter, the tires have deflated. This is because when you filled the tires in the summer, the air particles were warm which caused them to have more energy and move around faster, bumping into eachother more often. In the winter, the temperature of the air particles in the tire has decreased, causing the particles to move slower due to less energy. To keep pressure constand, the volume of the tire decreases.

Gay-Lussac's Law states that at constant volume, when the temperature of a gas increases, the average kinetic energy of the gas increases. With the gas particles moving faster, they will collide with the walls of the container more frequently, leading to a higher pressure. An example of this would be popping popcorn. As the water in the kernel of popcorn heats up, the energy of the water particles move faster, colliding with the hull of the kernel more frequently, causing an increase in pressure. Once this pressure becomes too high for the hull to handle, the kernel explodes into a piece of popcorn.

[|Wiki Assignment #1-TED Talk]
The video clip 'Jane Chen: A warm embrace that saves lives' caught my eye by its picture, which was a little baby that appeared to be in a sort of sleeping bag. After reading the short summary of the clip, I became interested in learning more about this incubator. In this video talk, Jane Chen explains how 20 million babies are born premature every year and of those, four million die. This is because the baby does not have enough fat on their body to keep itself warm. From this, the baby gets hypothermia. Incubators cost about $20,000 which is why you do not find them in foreign countries. Her team created this incubator that only costs $25. This incubator looks much like a sleeping bag which has a wax-like substance inside. When the substance is melted, it maintains a constant temperature for 4-6 hours. While watching this talk, I became aware of the issue of premature baby births. I also learned how this new product will help save many babies lives through the melting of a wax-like substance. I am now very interested in the sciences of an incubator. I am also interested in learning more about the development of a babies body.