Dana+H

=Wiki Assignment #9= 1. A concentrated solution is a solution that has a large amount of solute dissolved compared to the amount of solvent. A dilute solution has a small amount of solute dissolved in a large amount of solvent. 2. A strong acid solution contains an acid that almost completely breaks down in the reaction. A weak acid solution has an acid that does not fully ionize in the water. 3. A concentrated solution of a strong acid would contain many H and A ions and a relatively small number of H2O molecules. There would be v very few HA molecules. A concentrated solution of a weak acid would contain many HA molecules and a relatively small number of H2O molecules. Only a few molecules would have ionized, so there would only be a few H and A ions. A dilute solution of a strong acid would have a few HA molecules, but more H and A ions. These would be dissolved in a much larger amount of H2O molecules. A dilute solution of a weak acid would contain a very small amount of H and A ions a larger number of HA molecules, with both amounts being small compared to the large amount of H2O molecules. = = =Wiki Assignment #8= 1. When a system is at equilibrium, the concentrations of the reactants and products do not change. However, the system is still dynamic, with evaporating and condensing happening all the time. The reason that it is dynamic, yet the concentrations don't change is because the opposite evaporating and condensing processes are happening at the same rate. 2. An equilibrium expression is written as a ratio of concentration of products over concentration of reactants. The concentrations are raised to the power of their coefficient in the balanced equation. 3. **Homogeneous Equilibrium** Balanced equation: 2NO(g) + 02 <--> 2N02 Equilibrium expression: [NO2]^2/[NO]^2[O2] Balanced equation: CaCO3(s) <--> CaO(s) + CO2(g) Equilibrium expression: [CO2]
 * Balanced equation: H2(g) + F2(g) <--> 2HF(g) Equilibrium expression: [HF]^2/[H2][F2]
 * Balanced equation: N2(g) + 3H2(g) <--> 2NH3(g) Equilibrium expression: [NH3]^2/[N2][H2]^3
 * Balanced equation: 2NBr3(g) <--> N2(g) + 3Br2(g) Equilibrium expression: [N2][Br2]^3/[NBr3]
 * Heterogenous Equilibrium**

= = =Wiki Assignment #7= An example of equilibrium in nature is the water cycle. Water rains from clouds and gets collected in lakes and rivers. The water in lakes and rivers evaporates back into the atmosphere and eventually forms clouds, and the cycle repeats. The components of the system are still changing, but they are doing so at the same rate, so the equilibrium never changes. This is the same in an isolated chemical system, which also often includes a chemical in a gaseous state and a chemical in a liquid state. The liquid evaporates and the gas condenses, and eventually these things happen at the same rate. This is when equilibrium is reached.

=Wiki Assignment #6= Concentration Example When the reactants are more concentrated, that means there are more molecules within the same volume of chemical. Because of this, it is more likely that the molecules of the reactants will collide and cause the reaction to happen. The collisions will also happen more often. In the example, the reaction using 30% hydrogen peroxide happened much more quickly than the reaction using 3% hydrogen peroxide. There are more hydrogen peroxide molecules at 30% concentration so more collisions happen more often. Temperature Example When the reactants have a higher temperature, the molecules involved are moving more quickly. Because there is more motion, it is more likely for the molecules to collide and cause the reaction to happen. In the example, the light stick at the warm temperature glowed brighter because the molecules were moving more and the reaction causing the stick to glow was happening more quickly. The opposite happened with the cold light stick. Catalyst Example When a catalyst is added to a reactant, the catalyst lowers the activation energy of the reaction. This means that it takes less energy from the collisions for the reaction to happen, so the collisions that cause reactions happen more frequently. When the iodine is added to the hydrogen peroxide, the reaction happens much more quickly then when there is no iodine. Surface Area Example When the surface area of the reactant is increased, there are more collisions happening more quickly because the two reactants have a greater opportunity to tough and collide. When the flame is put on the powder in a mound, not much of the powder caught fire. However, when the powder was sprinkled directly into the flame, there is a large flame. This shows that the combustion reaction happens more quickly with more surface area.
 * Concentration:**
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 * Surface Area:**

= = =Wiki Assignment #5= 1. If a clean-up crew can reach the oil spill within a few hours of the spill, they use a containment and skimming approach. Buoyant booms float on the water and contain the spill, while boats suck or scoop oil from the water and into tanks. When the oil spills can not be cleaned as quickly, other techniques are used. For a minor spill, chemicals called dispertants break up the oil and it is dispersed into the air and water. If a spill is more serious, biological agents such as phosphorus and nitrogen are used. These biological agents break the oil down into natural components such as fatty acids and carbon dioxide.

2. - Solubility is the maximum amount of solute that dissolves into a solvent at equilibrium. Rate of Dissolution is the rate at which the solute dissolves into the solvent. - For most solvents, solubility increases with the increase of temperature, but for gases the opposite is true. Stirring does not have any affect on the solubility of a substance. Surface area also has no affect on solubility. For liquid and solid solvents, the rate of dissolution increases with temperature. For gases, the rate of dissolution decreases when temperature increases. Stirring increases the rate of dissolution. Surface area also increases the rate of dissolution. = = =Wiki Assignment #3= Greenhouse gases are molecules such as CO2, O3, H2O, and CH4, that re-emit light in the direction it came from. When the sun's light is absorbed by the earth, the earth warms and sends out more light in the form of infrared radiation, or heat. Those greenhouse gas particles in the atmosphere absorb infrared rays and re-emit them where they came from, sending the heat right back down to the earth.

I have heard that humans are the cause of global warming. I have also heard global warming doesn't actually exist, that the earth goes through warming and cooling periods constantly and this is just part of the cycle.

=Wiki Assignment #2= 1. Boyle's Law Boyle's Law Demonstration This demonstration shows that when the volume of the bottle decreases, the pressure increases and the pushes the gas up. Then, when the volume of the bottle increases again, the pressure of the water decreases and the gas expands again. This pushes some coloring out of the dropper.

2. Charles's Law [|Charles's Law Demonstration] This demonstration shows that when the temperature of the balloon decreases, so does the volume of the balloon. This happens because when the temperature increases, the gas particles move around less and get closer together. When the temperature of the balloon is increased again, the volume also increases.

=Wiki Assignment #1= Evan Grant: Making sound visible through cymatics

I chose this talk because the title interested me. I had never heard of this branch of science, cymatics, so I wanted to learn more. I wanted to see how sound could possibly be made visible and see examples of these experiments.

Evan Grant describes the science of cymatics, which is the process of visualizing sound by vibrating a medium of sand or water. Scientists have been exploring the effect of vibrations as long ago as DaVinci, who studied resonance. More recent developments include the experiments of Ernest Chladni, who first used the term cymatics. Chladni used a metal plate covered with sand to illustrate vibrations. He then bowed the edge of the plate with a bow from a violin and the sand made intricate patterns, changing by the frequency of the sound. The experiments have become much more advanced today and can show the shapes of musical masterpieces, and mimic natural shapes, such as snowflakes.

I thought this talk was fascinating. It was incredible to see the patterns that sounds make when put through cymatics machines. It was also interesting to learn about the practical applications of cymatics and how this science may help everyone in their daily lives.