Airbag Lab

The lab was done by using a plastic bag, with baking soda and vinegar reacting to produce carbon dioxide gas to inflate the bag. In order to calculate the correct grams of baking soda as well as the correct milliliters of vinegar we had to use math (stoich). The first step I used was to fill the container with water and use that amount to figure out the amount of volume available in the plastic bag. After this was done, I used pressure x volume in liters divided by .0812 x 294.15 kelvin = moles of carbon dioxide gas, I then used the mole number of carbon dioxide to work backwards to get the grams of baking soda. I then used the grams of baking soda which is the limiting reagent, and figured out the ml of vinegar that needed to be used. Overall the lab was a success and I passed the lab! lol

Airbag Video
Online lab help

Avagadro's Law

Avagadro's Law holds that temperature and pressure are constant, and the volume is directly proportional to the number of moles of gas present. Also, equal volumes of gases at the same temperature and pressure have the same number of particles.




http://www.chemteam.info/GasLaw/Gas-Avogadro.html

Charles' Law

The second gas law we covered in chemistry was Charles' gas law. Charles' gas law is when the volume of the container and the temperature of the gas is varied while the pressure is kept constant. The basic formula for this law is V1/T1=V2/T2, one important thing to remember is to change the temperature from degrees Celsius to kelvin. The conversion is done by adding 273.15 k to the degrees in Celsius. As the volume of the container gets larger the temperature gets greater as well, this is a direct correlation between volume and temperature.



http://www.docbrown.info/page03/3_52gaslaws.htm
Charles's Law Video 

Boyle's Law

So in our last unit of the school year we are learning about gas laws. The first gas law that we talked about in this unit is Boyle's law. In this gas law the temperature is kept at a constant. Therefore the pressure of a gas varys as well as the pressure. The rule of thumb is that as the pressure of the gas goes up the volume of the container goes down. The reason why this happens is the gas particles have less room to move therefore hitting the side of the container more often which increases the pressure. The standard formula for Boyle's law is P1(v1)=P2(v2).



http://www.one-school.net/Malaysia/UniversityandCollege/SPM/revisioncard/physics/heat/gaslaw.html

https://www.youtube.com/watch?v=N5xft2fIqQU

Energy Formulas

In this unit there are a few formulas that are used to decipher the energy transfer in certain systems. One formula that is frequently used in this unit is Q= MCAT, this formula is used to be manipulated o find out specific information regarding energy. Q stands for heat or energy in Joules, M is mass in grams, C is heat in Celsius, and AT is the change in temperature.  This formula can be practically manipulated for any question in this unit. Here is a link to a practice problem..............Q= MCAT Practice. There is also another formula that can be used to used to different substances and or objects releasing energy, in which they are set equal to each other. This formula is -MCAT = +MCAT the positive and the negative is for deciphering who is gaining and who is losing energy. These formulas can be manipulated like the basic MCAT to find certain variables.


http://1048believe.com/wp-admin/js/specific-heat-capacity-formula-physics

http://www.cbhs.k12.nf.ca/adrianyoung/Thermo2.pdf

Heating and Cooling Curves

Below are two examples of both a heating and cooling curve. As you can see, there are specific names for each phase change as a substance hits a certain temperature. You simply match up the amount of heat added with the temperature, and you are able to see the phase.




http://www.kentchemistry.com/links/Matter/HeatingCurve.htm
http://study.com/academy/lesson/what-are-heating-and-cooling-curves.html
https://www.youtube.com/watch?v=YG77v1PwQNM

Finished Project

Honestly my video is pretty bad :/ It was extremely difficult and hard to do in such a short amount of time, but it is finished.
Here's the link...... https://www.youtube.com/watch?v=_z5O2z_WO4o  Hope you like!

Project

We are starting the quarter with a project. The purpose of the project is to try to persuade the consumer that we should start using the renewable fuel of biodiesel to better our future atmosphere and air quality. In order to provide the best material possible I will provide kinks down below to take a look at.

http://biodiesel.org/

https://www.fueleconomy.gov/feg/biodiesel.shtml

http://www.afdc.energy.gov/fuels/biodiesel.html

About Biodiesel

Biodiesel is a fuel made from soy as well as animal fats

Biodiesel reduces greenhouse gases by 86%

Stimulates the economy

Reduces Caarbon dioxide in the atmosphere

Is a recycled fuel

Creates jobs in the United States





http://www.alternative-energy-news.info/technology/biofuels/biodiesel-fuel/
















http://www.ebb-eu.org/biodiesel.php

Hybridization

Hybridization is the idea that atomic orbitals fuse to form newly hybridized orbitals, which in turn, influences molecular geometry and bonding properties. At first, it was a slightly challenging concept to grasp. But with practice, it became easy and I began to realize the patterns that never change.



https://www.khanacademy.org/science/chemistry/chemical-bonds/copy-of-covalent-bonds/v/sp3-hybrid-orbital-jay-final
https://chemistry.boisestate.edu/richardbanks/inorganic/bonding%20and%20hybridization/bonding_hybridization.htm

Chemical Bonding Lab

In this Lab we were to apply our skills that we had learned from lecture in the previous days about Lewis structures and electron geometry. Electron geometry is just the type of format of the covalent bond based on the number of domains. I will provide material below to further expand your knowledge from this lab.

lone pairs explained 

Domains Explained 

Lewis Structure

The Lewis structure is a representation of chemical bonds and elements based on its valence electrons. Many of theses diagrams are used to help diagnosis the electron geometry of the covalent bond. Any easy way to do these structure is count all the the electrons in the atom, place least electronegative element in the center, and place electrons throughout the bonds.

 
Octet Rule

http://socratic.org/questions/how-many-valence-electrons-are-in-bromine
Co2 Dot structure Video

Periodic Trends

We learned periodic trends, and putting them to practice with a few activities. The first trend is atomic size, where atoms get larger because you move down a group, and also get bigger as you move from right to left, leaving the largest atoms in the bottom left corner. The next trend is ionization energy, which is the energy needed to remove an electron from a gaseous state atom, and it results in forming a cation. This trend is at its greatest in the top right. The third trend regarding only the s and p blocks, along with the two previous trends is electron affinity, which is the ease with which an electron may be added to an atom, creating an anion, otherwise, the energy given off when an electron joins an atom, and this gives off negative energy. This trend is also at its greatest in the top right. The final trend we learned about in our supplement is electronegativity, which is the tendency of an atom to draw electrons toward itself when chemically combined with another element, and this is greatest to the right and up, but does not include noble gases. 
This overall demonstrates all the trends:

Here are some practice links:
http://www.acschools.org/cms/lib07/PA01916405/Centricity/Domain/362/Periodic%20Trends%20Worksheet%20Answers.pdf
http://www.sfponline.org/uploads/71/periodictrendspracticesub1106.pdf

Quantum Numbers

Each element in every atom is assigned a set of four quantum numbers and no two electrons can have the same quantum numbers.
1. The first number is the principle quantum number which is the principle energy level.
2. The second number is the angular momentum quantum number which is the sublevel but the sublevels are assigned number. 0 is s, 1 is p, 2 is d, and 3 is f.
3. The third number is the magnetic quantum number which is determined by how much of the orbitals are filled
4. The fourth number is the quantum spin number which is either +1/2 if its the first electron in an orbital or -1/2 if its the second.
This link has practice problems with the answers so you can check if you get it right.

• 

Spec 20

We used a spectrophotometer in lab today. We found percent transmittance and absorbency of cobalt and chromium by placing a cuvette into the machine and setting a certain wavelength. Here's my data from the lab.

Cr Ion
Wavelength (nm)	% T	Absorbance
375	59.2	0.226
400	49.4	0.306
405	49.2	0.309
415	50.2	0.300
425	54.4	0.264
440	62.6	0.203
455	72.8	0.138
470	80.2	0.096
490	81.2	0.091
500	80.4	0.094
520	72.6	0.139
530	68.2	0.167
540	63.8	0.196
550	60.4	0.219
570	56.8	0.245
580	57.0	0.245
600	62.4	0.205
625	72.6	0.138

Co Ion
Wavelength (nm)	% T	Absorbance
375	98.8	0.006
400	92.4	0.035
405	90.0	0.047
415	86.4	0.063
425	80.4	0.094
440	66.0	0.180
455	49.6	0.305
470	40.2	0.396
490	32.2	0.492
500	30.4	0.518
520	31.6	0.500
530	38.0	0.422
540	47.8	0.320
550	58.6	0.232
570	78.6	0.104
580	85.4	0.069
600	90.2	0.045
625	92.2	0.036

And some pictures

Electron Configuration

The electron configuration of an atom is where the electrons are found and how many there are in an atom. There are four levels to describe the location of an electron in an atom: principle energy level, sublevel, orbitals, and spin. The principle energy level describes how far away from the nucleus an electron can be found. Its symbol is n. There are four different sublevels, s, p, d, and f. The first principle energy level only has one sublevel, the 1s sublevel. The second principle energy level has two sublevels, 2s and 2p. The third principle energy level has three sublevels, 3s, 3p, and 3d. The fourth and all subsequent principal energy levels have four sublevels, 4s, 4p, 4d, and 4f. Each sublevel ahs a specific number of orbitals, the s sublevel has one orbital that can hold 2 electrons, shaped like a sphere, the p sublevel has 3 orbitals that can hold 6 electrons, shaped like dumb-bells orientated perpendicular to each other around the x, y, and z axis, the d sublevel has 5 orbitals that can hold 10 electrons, and the f sublevel has 7 orbitals and can hold 14 electrons, both the d and f sublevels have complex shapes. Each electron is paired with another and they have opposite spins. 

When writing the electron configuration of an element the first number is the principle energy level then the sublevel then the number of electrons is the superscript. This link gives you practice writing the electron configuration for different elements.

Flame Test

This lab was really neat. We did this lab to help us understand how wavelength corresponds to color. In the lab we burned a few chemicals and recorded the color we saw then using the color we looked up the wavelength. 

Energy, Wavelength,and Frequency Calculations

All waves have wavelength, amplitude and frequency. If a wave has a short wavelength and a high amplitude it has high energy, but if a wave has a long wavelength and a low amplitude it has low energy. To find the speed of a wave you multiply wavelength and frequency together. Electromagnetic radiation moves through a vacuum at a speed of 3.00*10^8 m/s, so that is what we use for speed of a wave. You can also find how much energy is in a photon with a certain frequency. To do this you multiply the frequency by Planck's constant which is 6.63*10^-34 J*s.

 

This link gives you practice problems on how to find energy, wavelength and frequency, and it shows you how to do it if you get stuck.

Titrations Lab

We ran a lab this week similar to the one before, but this time to find the molar mass of an unknown acid. For this lab, we titrate an acid we are given to as I said before, find the molarity of it. First to start the lab, we had to standardize the base solution, so I weighed about 0.2g, added it to a Erlenmeyer flask by rinsing it with diluted water, added about 100mL of diluted water, added 2 drops of indicator, and  finally titrated it until it turned pink. We did this twice and averaged the two for our calculations. When the solution turns pink, we know that all of the KHP had been reacted. Next, we did the same thing by titrating the unknown acid that we had to weigh. Finding the molarity in the first two and solving for just the moles of HA is what was then used for more calculations. 
Here are some pictures from the lab:

Blame isn't really being assigned to anyone, but my lab partner and I (mostly her) broke and erlenmeyer flask. #chemfails :/

Percent Acid in Vinegar Lab

Over the last few days my lab partner and I have performed the Percent Acetic Acid in Vinegar lab. By standardizing a solution of NaOH with the acid potassium hydrogen phthalate, or KHP, in a titration we were able to determine the molarity of the NaOH solution. Using this standard NaOH solution, we were also able to determine the percent of acetic acid, HC2H3O2 in commercial vinegar.



Adding distilled water to the Erlenmeyer flask in order to dilute the vinegar



After adding two drops of the indicator phenolphthalein we were able to titrate the solution


After all of the titrations were complete, the calculations for the percent acetic acid in vinegar could be made by calculating the average molarity of NaOH and plugging that in to find the molarity of the acetic acid. The molarity could then be multiplied by the molar mass in order to find the mass of solute in the solution. With this mass the percent acetic acid in vinegar can be determined by dividing it by the volume of the solution.

This was helpful in calculating the percent acetic acid in vinegar

Titrations

Today's lecture in chemistry was over titrations and equivalence points. A titration is a technique that is used in order to determine the concentration of an unknown acid or base. During the titration, a neutralization reaction, or a reaction that uses equal quantities of acid and base, occurs. A neutralization reaction is reached once the amount of acid and base, with respect to concentrations, are equal and this can be seen when the solution in the Erlenmeyer flask turns a light pink. This change in color is caused by an indicator that is pH sensitive which changes the color once the reaction is complete. An equivalency point in a titration is when the moles that were originally in the solution are equal to the moles after the titration.

A titration is shown in this picture above. the base is in the buret, being kept there by the stopcock. The Erlenmeyer flask contains the acid which has an unknown concentration, this flask is placed right under the buret. The stopcock is then opened in order to allow the base to go into the acid until the color change occurs.
I found this site helpful in order to practice some titration calculations

ICE Box

We learned ICE box problems. These types of problems are designated solely for when you identify the acid or base is weak, but still want to find the pH of it. You cannot use the same system as you would for the strong acids and bases, but instead use this. To set up the problem you first write the letters ICE vertically along the left hand side. The I stands for initial, the C stands for change and the E stands for equilibrium, and the chemical equation is above the box, horizontally. Next to the I is always the molarity given to you in the problem, and going across will be two dashes, since no data will be shown there. Next, in the C column, you will place a -x. +x, +x, and finally in the E column you will add the two columns up. Then, this information will be put into the equation Ka= [H+][ClO-]/[HClO]. This will further turn into a quadratic equation when numbers are plugged in, and you must solve for x. An easy way to do this is to graph the quadratic and identify the zeros with a function on the calculator. The final step is to convert into pH with the equation pH=-log[H+]. 
Here is a picture and some links to visually understand and practice this concept:
http://www.chem.purdue.edu/gchelp/howtosolveit/Equilibrium/ICEchart.htm
https://www.youtube.com/watch?v=tT-2xk9ZG_A

H+, OH-, pH, and pOH

Today we learned how to convert between hydrogen concentration, hydroxide concentration, pH and pOH. We were able to convert between all of these using one original given value.
This picture shows how to get from each value to the next in simple problems.

Some problems require more than one step in order to get the answer. For example, if you are given the concentration of hydronium ions and asked to find the pH, then you need to find the concentration of hydrogen ions, or the pOH first.

This site helped me practice the conversions from this lecture.

Arrhenius and Bronsted-Lowery

We recently covered the difference between acids and basis, which I had some prior knowledge on. I learned that Acid and Bases can be defined in two ways, Arrhenius and Bronsted-Lowery. The major difference between the two is shown below. 

Arrhenius:
Acids produce hydrogen ions in solution (H+)
Bases produce hydroxide ions in solution (OH-)

Bronsted-Lowery:
Acids donate a proton (H+)
Bases accept a proton (OH-)

While grasping this concept, I found this link helpful

Solutions Stoichiometry

When calculating molarity, stoichiometry can also be used. There are steps to follow when using stoichiometry, one is systematic approach, and the other is the flow chart, which is shown below. This topic can be hard to grasp, so using these links can be helpful.

1. http://chemcollective.org/activities/tutorials/stoich/solution_stoi 
2. https://chemistry11mrstandring.wikispaces.com/Stoichiometry+Calculations+Involving+Molar+Concentration
3. https://www.youtube.com/watch?v=n5TaI_XR3y4

Dilutions and Lab

Today in class we completed an aqueous solution lab. We performed this lab to see how the concentrations of the solutions change in a serial dilution. We began the lab with 20 drops of food coloring in 10 mL of water. For the next solution we took 1.0 mL of the previous solution and added it to 9 mL of water. We continued this until the food coloring was no longer visible.

This link has practice problems for serial dilutions, and this website  and second website explains the topic more in depth. 

Molarity

Molarity is the molar concentration of a substance. Use the picture below to help you find the molarity.  This link gives you practice on how to find the molarity.

Solubility Curves

Solutions are made up of two parts the solute and the solvent. The solute is what is dissolved in the solvent. The solvent is part of the solution that is in the largest quantity. 

There is a limit on how much solute can be dissolved in the solvent. There are three stages of how much solute can be dissolved in a solvent: unsaturated, saturated, and supersaturated. The graph below is a solubility curve this shows what compound is unsaturated, saturated, and supersaturated.
This link shows you how to read a solubility curve and gives you some practice reading them.