Lab 7.1: Flame Test and Emission Spectra

The spectrum of light is often refered to as the "fingerprint" of an element. As each element moves through the ground state to the excited state the electrons absorb energy and jump to a higher level. This is shown in the electron configuration where the electrons seem out of order and moved into a new orbital as the electrons move higher up with more energy. As the excited element goes back to the ground state electrons go back to the original configuration emitting/releasing extra energy in the form of light called spectra. Each element had there own bright line spectrum making them unique from one another like fingerprints.

Enrichement:

1.The astronomer Pierre Janssen discovered helium after studying the Sun during a solar eclipse.The spectral lines, he discovered was not any known element. He said that there must be an element on the Sun that had never been seen on Earth. The name comes from the Greek word helios for "sun."

2. A blue shift is when the spectra wavelength signals are shortened meaning the object is getting closer and the light emitted is on the blue end of the spectrum. The opposite effect called res shift is a longer wave length emitting light on the red end of the spectrum telling you something is moving farther away from the observer. The red shift and blue shift are evidence that the universe is expanding because all the galaxies in the universe are red shifted. Hubble approximated the relationship between redshifts and the distance with the formulation of Hubbles law.

6-2: Acid and Base properties

Electrolytes are ionically bonded with a positive and a negative ion. All electrolytes can dissloved in water, so when it dissolves it forms an ionic solution.The electrolytes is a substance the ions break apart when dissolved in water and the charges are free to move and allow the electric current to move through it. On the other hand non electrolytes are not soluble in water and the ions do not break apart to allow an electric current to travel through them. Electrolytes are salts in the body that can conduct electricity and are found as fluid, tissue and blood In your nervous system electrolytes conduct electricity and allow the passage of electric currents to travel through your body to signal a function for your body to preform.

An indicator changes the acid or base a color according to their ph. A ph of less than 7 is a acid and a ph of more then 7 is a base. Acids contain the ion H+ and bases have the ion OH-. An indicator is a natural die changing different colors because of the sensitivity to the ph. An indicator is a weak acid and when adding  to much to a solution you may interfere with the chemical reaction. When tasting the acid it came off as sweet and sour like sour patch kids candy and the base was more bitter and salty is like baking soda. When adding an acid and base together the opposite ions bond and form a neutral solution with a ph of 7 this is a double replacement reaction resulting in a salt and water solution. In our lab we added magnesium powder to the acid we saw a bubbling and fizzing reaction and when added to the base you saw no reaction. This is because both magnesium and the aid are positively charged so you see a reaction when added in base these opposite ions attract and form a neutral solution of salt and water. When determining which solution was which my thought process was whatever takes more ind actor to change neutral color is the solution with the highest concentration(most moles of solution).

Enrichment:
A real definition of an indicator is when the natural pigment in the acid or base it may gain or loose hydroxide (OH-) depending on the ph. This changes the wavelengths of light reflected off the compound creating the color changes for different phs.

6-1: Double replacements

While many of my predictions matched up to the results, there were others that did not match.The whole Copper Chloride row, i predicted when reacted with another chemical would produce a compound that was soluble. It turned out that actually none of the chemicals mixed with Copper Chloride produced that compound that was soluble, and no reaction took place.Another one that didn't match up were Potassium Iodide with Potassium Dichromate, and Potassium Iodide with Copper Chloride. I think that the first one didn't match up because when they were put together the same thing was formed that had already been present.

When using the precipitation reaction nitrate is filtered out of waste water. In table F it forms a soluble compound so it would stay in the water and need to be taken out by being evaporation. Sulfate is a good ion to use as a percipitate because it isnt a soluble ion. Meaning that it wouldn't mix in with the rest of the soultion, so it could be used to seperate whatever needed to be taken out.

5-1: Rates of Reaction

In this lab we tried to see how temperature, concentration, and surface area affect the rate of the reaction between vinegar and alka seltzer. In our experiment we first broke each of the alka seltzer tablets into 4 pieces. For the concentration procedure we first measured out 15 mL of waterand then and poured it in a film canister adding the quarter tablet to it. The cap was placed on tight, and we timed for how many seconds it took the cap to pop off. Then we continued the experiment by intensifying the concentration of vinegar, again recording the reaction time. The varibles held constant was the uncrushed 1/4 tablet. For the next two experiments the variable tested was the water temperature, and the surface area of the tablet. For the water temperature, we needed to keep the amount of water, and a non crushed tablet the same through all of the different trials because if we changed these things, or results would have been changed we would not know what had effect on what without a constant. Student B had the best method for this experiment because unlike the other two students, student B changed the temperature variables in order to get different outcomes. This is an important method because if you change the temperature, the rate of the cap on the container will either come off faster or slower depending upon the temperature it's at. If you varied mulitple variables at the same time you'd have multiple things going on and you wouldn't be able to figure out what caused a change due to the fact that other variables are changing too.

Each variable has changed the rate do to particle collisions due to effective collision. This means that the particles have collided in such a way that there will be a chemical reaction. The changes we made in the lab, influence the number of effective collisions that were occurring. This happens because each variable alters the effectiveness of the chemical reaction.Each particle changed the rate because as the temperature increased, the time it takes for the cap to come off was  faster. As the temperature decreases, the cap comes off at a slower rate. With the higher concentration of vinegar that is added with less alka seltzer the cap to comes off at a slower rate because the alka seltzer is what triggers the whole experiment. What I expected to happen did happen; I predicted that the higher the temperature, the faster the cap of the container would come off and the lower the temperature, the slower the cap of the container would come off.

Enrichment:
An example of a catalyst is the catalytic converter in a car. This is coated with platinum to reduce carbon monoxide emissions. Catalysts are used to speed up the rate of reaction it reduces the required activation energy needed for the reaction to occur.

4-2: Heating and Cooling curves

In this lab, we experimented and observed the changes in the energy of the lauric acid as it changes from one phase to another.

Step 1) Measure 5 grams of the lauric acid and put it into a test tube.

Step 2) You then begin heating the test tube of this substance in a beaker of hot water and record the temperature every 25 seconds with the thermometer stirring the luric acid.

Step 3) Then, you repeat this process in a container full of ice and recording that data every 25 seconds.

Step 4) After all this is finished, we graph our data and begin to observe the curves of those two experiments.

We found that the melting point of the lauric acid was about 50 to 51 degrees celcius and the freezing point was about 43 degrees celcius. These temperatures are close but arent the same like they should be.melting The melting point is going from a solid to a liquid, and the freezing point is just the opposite process, going from a liquid to a solid. These temperatures should be the same because they both involve the same amount of energy as it goes from one state to the other. They're two phases that just have different direction of the flow of energy

Kinetic energy is the energy in a substance due to it's particle movements. In my heating curves graph it is when the curve is increasing and in my cooling graph the curve is decreasing. Potential energy is the energy that is stored in a substance. My potential energy within the luric acid shows in my heating graph as an increasing curve and is a decreasing curve in my cooling graph.

Enrichment:

Lauric acids actual melting point is 44 degrees celsius. I think I was too high because my data could of been an error in recording temperatures or the timing in taking the temperatures.

Lauric acid is used in many oils, humans milk, cows milk, and goats milk. The chemical formula for lauric acid is C 12 H 24 O 2 and the structure is polar carboxylic acid head.

Lab 4.1: Having fun with air pressure

1) When there is a decrease in pressure the volume of the balloon to increase due to the fact that there is less air pressure. The molecules inside of the balloon spread out to match the pressure outside the balloon cause the balloons volume (size) to increase.

2) If and when you add more gas to a bottle the pressure will increase inside with less room the molecules will collide with each other more creating higher pressure.

3) As the volume of a cylinder increases the pressure will increase in order to keep the pressure inside the cylinder equal to the outside pressure the same before the volume increased.

4) Increasing the pressure in a tire due to adding more gas, will cause the volume to increase because the tire expands in order to match the pressure outside the tire.

5) As the temperature of a closed container of water is increased the amount of water vapor above the water causes an increase in vapor pressure. The higher the temperature, the more water that will be vaporized which means there will be more gas molecule collisions meaing air pressure increases inside the container.

6) As the air pressure above a liquid is increased by adding more air, the boiling point of the liquid will increase because as the pressure increases the boiling point increases relatively to the pressure. This is because with a higher pressure it is harder for the molecules to separate with less room and become a gas.

7) If a balloon filled with air is taken under water its volume will decrease because there is higher pressure below the water the balloon will get smaller to match the outside pressure. Providing less room inside the balloon allows more collisions increasing the pressure inside the balloon to match the outside.

8) The temperature of a beaker of boiling water will remain the same as more heat is added because as it boils it remains the same temperature breaking the bonds of the molecules to create gas.

9) Hot air rises because it is less dense with the cool air around it. More energy = less dense and less dense = more it will rise.

10) When heated, the volume occupied by air in a balloon will increase because the more and more molecules there are inside of that balloon collides creating higher pressure causing the balloon expand more / have a higher volume.

Enrichment:
In the picture of the tanker car, it was sunk in due to the air pressure difference. As you flush the tank out with hot water, it caused more water vapor due to the temperature of the water. As the water vapor temperature  decreased, the water vapor went from a gas to a liquid. When water vapor pressure became nonexistent and all was left was water making pressure considerably different causing a vacuum effect. The air pressure outside of the tank was able to crush it due to a higher air pressure outside the tank.

Lab 3.1: Properties of Ionic and Covelant Compounds

1.The common properties of ionic compounds are that they are hard, have a high melting/boiling point and no conductivity except when dissolved.
 

2.The common properties of covalent compounds are that they are soft and some brittle, low melting/boiling points, some dissolve and some don't and don't conduct electricity.

3. Ionic compounds are between metals and non-metals. During this form of bonding the valence electrons are taken from the metals to form a stable octet for both metal and non-metal.

4. Covalent compounds are between non-metals and non-metals who share electrons to form a stable octet neither strong enough to pull the valance electrons away from each other.

5.No matter what, broken up or in a compound, the covalent bonds lack any charge because technically they're not losing or gaining any electrons(because they are both nonmetals) so they do not have a charge.

6.When ionic bonds are broken in a solution it contains ions which gives them an electrical charge but when you compare it to a solid, it's the complete opposite. then the elements still have charges because one element had to lose electrons and one had to gain giving the individual particles a charge, making them conduct electricity

Enrichment:

Electrolytes means that an ion is electrically charged. Electrolytes is used to maintain voltages across the cell through cell membrane to other cells leading to messages towards the brain and muscles.You loose electrolytes in your sweat, in order to maintain this energy you can replaced these lost electrolytes through drinks like Gatorade. Sugar is also used for extra energy but is mostly used to make the drinks taste better.The electrolyte substance usually used by your body is potassium and sodium you must replace these electrolytes in order to keep you body constant.