Lab 10.2: Solubility vs. Temperature

Our graph was similar to table G in our reference tables but because we only had four points our graph it showed some differences and created some room for error. Only using ten grams of solvent instead of one-hundred on our graph created less accurate results as compared to the one on table G.
In our experiment the temperature of water impacted on how quickly solvent dissolved. The more KLO3 (greater concentration) the more time it takes to dissolve. To dissolve more quickly we put the test tube into a hot water bath to increasing the temperature of the solution. When the solution is liquifyied the particles make more collisions, and they are also more efficient(effective). At the liquid stage the particles are less attracted to each other than at a solid. bB crushing the KLO3 you could increase its surface area and help to speed up the rate of reaction. In our experiment the solution was unsaturated when the KLO3 was undissolved at the bottom of the test tube. It was saturated when the KLO3 had completely dissolved into the solution.

Enrichment:
Rock candy is a saturated solution. Yo saturate the water you add as much sugar as it can take, but then heating the water you create more space for sugar creating a supersaturated solution. You would then add the string into the water on which the rock candy would form as the water cools the sugar to come out of the solution forming a precipitate which we know as the crystals of the rock candy. This is because the super saturated solution has more sugar in it than it can possibly hold.

Lab 11.1: Corrosion of metals

1.
a) The penny wrapped in steel wool was less corroded then the unwrapped penny.
b) This is sacrificing metal technique because you did not coat the penny with a metal so only the outside only corrodes you merely wrapped it leaving some parts of the penny showing and corroding. The iron was "sacrificed" so most of the penny was protected(steel wool was corroded in place for the copper in the penny).
c) This works because iron is more active on table j than copper so the copper won't react with the rain. The active iron bands react with the rain and become erroded but leaves the copper unharmed. Hence them being checked and replaced regularly.
2.The corrosion is occuring because the aluminum is more active than the iron that was surrounding it; yhe Al ion and the iron are reacting because the metal is higher on table j.

3. The caulk would've created a barrier between the Al and Fe. So there would have been a coating and less corrosion would have had taken place.

4.
a) Corrosion is when a metal and an ion reacting cause the metal to errode.
b) Chemists have created different ways to outsmart it by putting the iron is the copper made statue of liberty or using caulk between the metals and ions. This coats the metal they want to protect with another metal so that metal will corrode instead of the one you need.
Enrichment:
Al+O2---> Al+3 and Fe +Al+3 ---->Al +Fe +3.
Aluminum is represented by A and iron would represented B.

Lab 11.2: Table J and Metal Reactivity

1.    a) The nitrate ion known as a “spectator ion” is an appropriet title because as examined in the reaction equation nitrate stays the same befor and after the reaction. 

     b) In the reaction between magnesium and silver solution, silver was oxidized and magnesium is reduced. 

2. Metal X and metal ion Y⁺² will react, when X is higher then Y based on Table J.

3.  1. An activity series is a list of substances ranked in order of decreasing relative reactivity. The most metallic elements of group 1 have the most relitive reactivity nonmetalic elements at the bottom of table J are the least reactive(left side of table s moving towards the right go from most metallic elements to non metallic).

     2.   Which ever metal is higher on table J is more reactive then the metal below it.

4. Gold, silver, and copper are on the bottom of table j suggesting the are the least reactive metals. This made it easier for humans to discover these metals because they havent reacted with there surrondings. Other metals (lead, tin, iron, mercury) that are more reactive were dicovered much later because you must go deeper into the surface to find these metals nonreactive to the surrondings.5. 

• Copper was smelted from its ores Malachite and Azurite in anctient times. In a pottery kiln with charcoal these elements were fired and reduced to metallic copper.
• Bronze is made of copper and tin melted together at high temperatures.

Enrichment:

The light sensitivity of the silver halides exposed to a light, a chemical reaction darkens the film to produce an image. AgCl used in photography, consists tightly packed ions of silver and chlorine, when film containing Ag+ and Cl- is exposed to light energy, the chlorine ion's extra electron captured by a silver ion. When silver metal is produced as a result of the electron capture, it forms a dark image on film.  Ag+ has been reduced to Ag (metal), and Cl- has been oxidised.

Lab 10.3: Titration+ Colligative Properties

• When measuring the concentration of base (NaOH) there was not much difference in the readings of each sample. This wasnt surprising since we were doing the same procedure with the same material three times.Some possible errors that may have caused differences in the values are not reading the graduated cilinder to an exact decimal amount or not reading the value at the exact time of post-neutralization (8 pH). To fix this you can have more then one person observe at the same time as you to catch the right value right at nuetralization and also have a graduated cylinder with more measurement marks for a more precise measure rather then geuss the value between two lines.
• Antifreeze is an important for your engine in different climates. When the temperature gets cold we need something that has a lower freezing points to still finction in cold weather. Antifreeze has chemicals that will remove the access metal and other substances from your car engine, without freezing in the pipes of the engine. By having molecules that can be dissolved into ions and are soluble in water in the antifreeze, the freezing point is lowered because of the energy transfers. In order for water to freeze, a set ratio of water molecules needs to form a specific crystal  If extra ions are in the water, the polar ends of water molecules will attract to these ions more so than they will with other water molecules. Therefor the antifreeze will not freeze the pipes within your car while in use. The opposite happens when it is really hot out. When the temp may be above the boiling point of water the extra ions increase the boiling point because the attractions are stronger than standerd hydrogen bonds between water molecules. So with stronger bonds between molecules, the more energy will be need to break them apart meaning a higher boiling point. Antifreeze is needed in order to raise the boiling point of the water above the temperature surronding it so that the water solution created stays a liquid and allows your car to function.
  
• Enrichment: Ice cream.
  The dissolved sugar, by getting in the way of the molecules that bond together to form ice crystals lowering the freezing point of the cream. This is why the cream solution will not freeze at the same temperature that water freezes. When the temperature of the cream gets low enough the water molecules have slowed down enough thso now their attraction becomes stronger than the disruptive influence of the sugar. For the temperature of the cream to get low enough  they crystallize, the water molecules are removed from the solution which means the remaining solution gets more concentrated with sugar so its freezing point is even lowered further.

Lab 10.1: Solvents (Like Disolves Like)

1. Salt and sugar are definitely polar because they have a strong attraction to the polar water(like dissolve like).The samples with the other solvents are non polar and since the polarity is unalike they do not dissolve in the solution.
2. Vegetable oil is definitely non polar because they have a strong attraction to the non polar hexane(like dissolve like).The samples with the other solvents are polar and since the polarity is unalike they do not dissolve in the solution.
3. Ethanol has a polar and non polar end since it only can slight dissolve both non polar and polar solutes.
4. Ethanol could dissolve in both water and hexane since it has a polar and non polar side of the molecule it allows it to dissolve with polar water and the non polar side of hexane. This makes the solution slightly soluble as only one side of the molecule can be dissolved with like side of the molecules polarity matching the solvent.
5.  

	Type of Molecule	Solubility in Water	Solubility in Hexane
NH3	Polar	Soluble	Insoluble
I2	Non polar	Insoluble	Soluble
HCl	Non polar	Insoluble	Soluble

• 6. Ionic materials dissolve well in water because they are both polar. Hexane is non polar, solutes dissolve in other solvents of the same polarity as themselves.

Enrichment:

Nitrogen, oxygen, and carbon monoxide are all non polar so they do not dissolve in the polar water, like dissolve like. Oxygen is produced for fish by the plants who use carbon and carbon dioxide is stored in water these ions are an important part of natural buffers that prevent the water from becoming too acidic or too basic for aquatic life to live it.

Blog 9.2: LeChatelier's Principle

When HCL is added to the system the system shifted to the right to balance out the HCL indicted by the dark blue color change this means concentration of Cl- ion increased.

1. Since the system is exothermic when heated the heat is added to the reactant side of the system. This causes the system to shift to the right (indicated by dark blue color).
2. If the reaction is endothermic the reaction has more potential energy on the reactant side of the system. This means the heat of reaction has a positive sign because it is storing(gaining) energy. If the reaction is exothermic the potential energy decreases because it is being released in the form of heat this is shown on the product side of the system. This means the heat of reaction is negative because it i loosing energy.
3. Ag+ and Cl- when but together do not create a soluble compound according to table f. This was shown in the lab when mixing the silver with chlorine you are left with a cloud showing in the mixture showing they are creating a new compound and not mixing together. The solution around it was light pink this indicates a shift to the left decreasing Cl- to balance out the system.

Station 3 question:

1. When increasing pressure the gas bubbles in the soda go away to put the solution in equilibrium. When you decrease pressure you give more space for air bubbles to form to shift the system back into equilibrium. This is the same as when you open a soda you are decreasing the pressure of the soda inside the can so the formations of bubbles to balance out the can cause it to "effervesce" (release gas).

Enrichement:

1. Chickens pant out CO2 gas.
2. When the CO2 decreases the equilibrium of the system shifts to the right.
3. When the system shifts right it causes a decrease in the amount of CaCO3 (egg shell) produced by the chicken.
4. The panting resulting in thinner egg shells because as a result of having less CaCO3 produces less egg shell for the eggs this means the eggs have to have a thinner shell.
5. To insure their chicken produce normally think egg shells in warm weather farmer could air condition the chicken coupe. This takes advantage of Le Chatelier's Principle by manipulating the temperature of a system to achieve the results you want.

Lab 9.1: Heat of Solution (Delta H)

1. In the solution of Ammonium Nitrate(NH4NO3) and water (H2O) the process that occurred was endothermic. The direction of heat flow was pointed into the solution absorbed by the process making the system and its surroundings a chilled temperature.

2. Error may have been from the rounding of the decimal place used by the thermometer when calculating the solutions temperature. Also we could not calculate for the heat absourbed by the sides of the cup and the thermometer.

3.A.)If the room temperature was ten degrees colder the total heat would have been different  and less energy would be used for the change in temperature (smaller delta H)because the change in solution was endothermic the temperature is already decreasing.

B.)If you added less chemical but you still knew how much you add, the q value and the moles of solute would be lower (lower concentration) but because they are going to proportionally lower the reaction is smaller causing a smaller change in heat (Delta H).

C.)If you added 40mL of water but thought you had 50 mL the change in heat would appear to be less because you have less water to change the temperature of the reaction. Less water equals a smaller change in temperature. 

Enrichment:   In Florida farmers spray their trees with water to protect the trees from being damaged. This helps the trees when the weather gets cold in order to preserve the tree and keep it healthy for the farmer. When something freezes (mist sprayed) it creates an exothermic reaction, this causes the realease of heat. As the heat is realeased it prevents the trees from freezing throughout the cold weather.

Lab 8.2:Hydrocarbon Properties

When the particle attractions are stronger, the molecular size of the particle is larger. This effects properties like boiling point. When the attractions are stronger the size of the molecule increases creating more viscosity. This means they'll be hard to take apart because there bonds are stronger. It will take more energy to break these stronger bonds so the boiling point is increased. When the particle attraction is lower so is the boiling point because it takes less energy to break the bond creating less viscosity.

Enrichment:

Before the oil can come out of the ground it has to be found.Geologists look at surface rock and soil types to determine where the oil might be located. Modern oil geologists examine surface rocks and terrain, with the addition of satellite images or locate oil using Vibrator or Thumper trucks to cause vibrations in the earth which are listened to by geophones. The data is processed by computers into dimensional displays that are seismic lines.

When it is time to dig into the ground for the oil, the land has to be flat and cleared. After the well has been drilled, a measuring device is lowered into the hole and information is gathered about the properties of the earth such as density, type of rock present, and what fluids the rocks may contain.The drill used requires water, so there has to be a water source. A reserve pit is dug to put the rock and mud that come up with the drilling. Now they drill many hole to place the rig and support the main drill.

When they are ready to drill, they set the drill tip in the hole and begin drilling. They add and remove pieces of the drill as it goes deeper. When the drilling is over a cement pipe goes down the hole then allow the oil to flow. Then they build a cement well directing the oil  into the well. The pump they place into the well that sucks out the oil.

Lab 8.1: Percent compositon

Some source of error in the experiment may be from when chewing the gum. When chewing the gum you may be consuming not only the sugar but fragments of the gum of itself this may make your measurement for sugar higher, since more weight is missing from the gum. Another source of error in this experiment could be how long you  chew the gum before all of the sugar is dissolved. A person might think that all the sweetness is gone, and they weigh the gum, when really, some sugar is still may be left this would make the measurement for sugar less. The percentages of sugar is effected by this error becoming a higher percentage of sugar with more weight lost and a lower percentage of sugar with less weight loss.

Enrichment: Blogs help us look back on what we did in class sometimes clarifying the information we learned or review it and sometimes the assignment may be easy and quick. Gaining access to a computer may be not accessible to every student some may also like writing better then typing. Lastly enrichment i find is the most time consuming at times and least helpful. I find it sometimes unnecessary it may be more useful if it connected our chemistry topic to our everyday lives. Not enriching us further about other chemistry experiments hard to understand and not necessarily needed to be informed of.

Lab 7.4: Reactivity of metals

1 and 2. Elements that are in the same group have more similarities than elements in the same period. Elements with the same number of valence electrons and similar properties are most similar. These similar elements share the same characteristics and reaction times.This can be proved from the data we collected when metals were being place into water and phenolphthalein.When the data was collected the six elements could be easily placed in three different groups based on properties observed.Group 1 (Na, K, and Li), properties for this group were started with each containing one valence electron then observing that the element reacted fast with the air, the elements floated in water, an exothermic reaction,and the water (phenolphthalein turned pink) meaning that the element is basic. Knowing these similarity's it can be concluded that all of these elements are in Group 1.The elements in our group 2 (Mg and Ca) also shared many identical properties and both had valance electrons of 2. And finally, the group left had only contained the element Al. Al had different properties than all the other elements, also had a different valance electron valance electron of 3.

 

3.When an element of sodium reacts with an non-metal:

a) the sodium atom will want to lose1 electron(metals loses electron) so that it can get to a stable octet.

b) the sodium ion will become positive ion called a cation. This is caused by loosing an electron there is one more proton, making it positive.

c) 1+

d) Its new electron configuration would be 2-8 that of Neon

e) The sodium ion will be more stable because it has 8 valance electrons resulting in a stable octet. 

Enrichment:

Alkali metals almost always form ions with a positive charge of +1, and are so reactive as elements that virtually all occur in nature only in compound form. Sodium a highly reactive element is in its pure form reacts with elements and moisture in the air almost immediately. It is more stable in compounds, so this is how it is found in nature.Pure sodium metal can be prepared by the process involves the electrolysis of NaCl mixed with proper amount of CaCl₂ to lower the melting point of NaCl. this process produces up to 99% pure sodium metal

7-2 Atomic mass of Pennium.

Pennies were good as isotopes because depending on the generation pre or post 1982 the penny contains a different ratio of zinc and copper.The new generation penny with less copper can be considered an isotope of pre 1982 penny's almost made of pure copper. A problem that can occur using penny's as an isotope is that they don't have a constant (like atomic number) like real elements and their isotopes.
1.The atomic mass is 35.45 amu. You multiply the mass number by the abundance percentage and add them with the abundance of the other isotope times its mass. Since the atomic mass is closer to Cl-35 it shows that it is more abundant then Cl-37.
2.Cl-35 and Cl-37 both share the same number of protons and neutrons within the nucleus. The isotope of Cl-35 is Cl-37 this happens when there are more neutrons in the nucleus added to the atomic mass.
3. Mass number and atomic mass differ in that atomic mass is the mass of one element, simply the elements wieght. The mass number isthe added wieght of another individual element. For example CuCl2 (copper chloride) mass is the added mass of Cu's atomic mass times how many Cu atoms you may have plus that of Cl because of the ionic bond you have to elements to add.
Enrichment:
1. A spectrometer is an instrument used to measure  characteristics of individual molecules. A mass spectrometer converts them to ions so they can be moved  and manipulated by electric and magnetic fields.
2. Natural uranium is only 0.7% uranium-235, a type of uranium that undergoes fission in this type of reactor.The reactor uses Uranium as fuel, and  heat is generated by nuclear fission (neutrons smash into the nucleus of the uranium atoms) split roughly the uranium atom in half and release energy in the form of heat the rest is U-238.Modern reactors use "enriched" uranium fuel, which has a higher proportion of U-235.

7-3 Periodic trends Activity

• Atomic radii trend decreases as you move from left to right. This is because the left of the table contains metals with a weak attraction for electrons. Meaning the electrons radius is farther away from the nucleus this is what makes it easier for metals to loose electrons.The heavist elements in a period have the smallest radii because the electrons are more attracted and closer to a larger mass pulling the electron shells closer.
• Elements at the bottom  of a group have the lowest electronegativity because it is the most metallic having the smallest ionization energy Making it easiest for the element to loose electrons.
• The non-metals are harder to take an electron away than metals because non-metals want to gain electrons, whereas metals want to loose their electrons.
• Trends are referred to as periodic because it represents a pattern that happens in the elements throughout a certain period hence the "periodic table".

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.