Who Cares About Titration?

Many industries use titration to determine the concentration of their products before selling. You might ask, what exactly is titration? Titration is a measured amount of a substance of an unknown concentration is added to a known volume of a second solution until the reaction between them is just complete. The concentration of the unknown substance can then be calculated. Titration is used in industries because it makes for quick determination of concentration of unknown solution. This allows a manufacturer to determine whether the manufactured substance meets the required standards or not.

Set up for the titration lab.

Titration can be used to determine the amount of citric acid in fruit juice. This is achieved by doing the following procedures, first, get approximately 50 mL fruit juice. Second, rinse a 10mL pipet with two small portions of HCl. Next, pipet 10mL of fruit juice into a clean Erlenmeyer flask. Add 20mL of deionized water and three drops of phenolphthalein. Lastly, add 1 to 2 portions of sodium hydroxide solution from the burette to the juice sample while swirling the flask around. As the titration process begins you will begin to see a pink coloring as the NaOH hits the juice. As you get closer to the end of the titration the pink will slowly spread throughout the solution at this point you should begin adding the NaOH in slow drops. The end point is when the pink color stays for 30 seconds or longer.  From there you calculate your concentration from the titration.

 

The Airbag

Have you ever wondered how an airbag works? Well the airbag is composed of three parts, the bag itself, which is made of thin, nylon fabric and is folded into the steering wheel and the dashboard. The second part is the sensor, which tells the airbag when to inflate. Lastly, there is the inflation system. Inside the inflation system sodium azide and potassium nitrate react quickly to form a hot nitrogen gas. This gas is what causes the bag to expand and burst out of the steering wheel or dashboard. After a second, the air in the bag is already deflating, this is because it has tiny holes and its to get it out of your way.

The process of the reaction inflating the bag applies the gas laws because if refers back to the ideal gas law of PV=nRT. Because it shows the relationship of the pressure and volume of the airbag as it’s inflating.

Links: http://www.chemistry.wustl.edu and http://www.howstuffworks.com

3 Questions 12/13/13

1. This week was my Christmas choir concert and it went great! I completed taking my EOC for English and U.S History.

2. Recently I have learned High School can be very stressful, not only because of the work but also because of the people. I have learned that it is hard to make time for everything and for everyone, but you gotta think about whats going to help you in the long run. Is spending more time with you friends more important than spending time on your school work? Hmm mind bottling…

3. Next week I plan on not totally bombing my chemistry finals and study till my brain wants to explode. Also try and do good on my vocab test and test on my book in English. Hopefully it’s a good last week of school before the break!

3 Questions 12/6/13

1. This week I finished selling my fundraiser for choir. I also finished my second essay for honors English. Lastly I participated in spirit week, and getting ready for the state football game!

2. Recently I have learned about Thermochemistry; Endothermic, exothermic, specific heat and enthalpy. In English i learned that while in a theater you should never say Macbeth because it is bad luck and weird things happen.

3. Next week I plan on doing good on my chemistry test and on my end of coarse exams.

Baby Bottle Lab

This past week in chemistry we had to do a baby bottle lab. Our objective was to find the right ratio of baking soda and vinegar to make our baby bottle shoot out and go 600cm.

I was lucky and was able to make my bottle go 600cm on my first try. I had filled my baby bottle half way up with vinegar, which was around 5 1/2 ounces. and i filled the nipple of the bottle almost all the way full with baking soda. After watching other classmates, it seemed as though you couldn’t have way too much of one substance.

This led to limiting reactants, which we learned after doing the lab. Limiting reactant is the substance that is completely consumed or used up during a chemical reaction. Depending on the amount of either substance used, determines what the limiting reactant is going to be. If we were to do the experiment again, I wouldn’t change a thing because every time I was able to make the bottle go 600cm.

3 Questions 4/1/13

1. This week I was able to finish my rough draft for my essay in English. I succeeded in making my baby bottle go 600 cm for a chemistry lab. And did good for my choir concert on Tuesday night.

2. Recently I have learned stoichiometry in chemistry and also an in depth understanding of the great depression in history.

3. Next week I plan on finishing my final draft for my essay. I plan on retaking a quiz in chemistry on Wednesday. I also plan on attending practice everyday this week and Friday go to the Mayfield vs Cruces game!

3 Questions 10/25/13

1. This week I was able to get a sponsor for MHS Choir. I finished my planning and started paragraph one of my essay for English. I also didn’t miss a single practice this week.

2. Recently I have learned about the mole in chemistry and have started learning stoichiometry.

3. Next week I plan on having my glog ready on time, to turn it in. I plan on completing my essay on Great Expectations by Charles Dickens, by Friday.

3 Questions 10/18/13

1. Last week I completed on memorizing most of our concert songs for choir. I went to the orthodontist, to find out my teeth are doing great. And i managed to get through another week of school.

2. Recently I learned that when lifting weights, don’t ever lift with the wrong technique, my lower back has been killing me!

3. This coming week I was planning on starting my essay for English and watching the new movie Bad Grandpa by the end of the week or go to the football game.

The Mole…In All Its Glory

Aah The Mole, not the mole that burrows in the ground, but the mole in science! A mole is a unit of measurement used in chemistry that is exactly 6.02×10^23. The mole was first thought of by Avogadro (an Italian chemist) and represents the number of molecules in a substance. After working with the mole in class the past couple of days, its surprising how big a mole actually is. A fun fact that helped me realize the enormity was, if a mole of pennies were divided up and given to every person on the earth, each person receiving 1.5×10^14 pennies. Personal spending at a rate of one million dollars a day would use up a persons wealth in just over two thousand seven hundred years. It would be nice never running out of money as long as you live but the earth would be covered in copper pennies to a depth of 420 meters. Hard to believe a mole is that big huh? But the mole helps to calculate the amount of smaller particles such as atoms. Not only that, but since the mole is consistent it helps when converting from atoms or molecules to grams. Common sense when talking about the mole is, a mole of one thing is the same as a mole of another.                                                                              

How To- Percent Composition

Today I get to be the teacher, and I am going to teach you all about percent composition. Percent composition is a process where a sample of a material is analyzed by its composition. You can find the percentage of the mass of a compound that comes from each of the elements in a compound by using a simple equation. The equation is: percent of element= (number of atoms)(atomic weight) divided by FW of the compound x100.

The picture is a better visualization of what I wrote above.

An example of when you would use percent composition, is lets say, your trying to find the percent/amount of carbon in ethane. The formula for ethane is C2H6. You find the atomic mass of carbon, which is 12 and the atomic mass of hydrogen, which is 1. Then you know you have two carbons and six hydrogen’s by the subscripts. You add the two masses together, 2(12)+6(1) and it totals to 30. So your total mass of ethane is 30g. Now since you want to know just the percent of carbon, this is where percent composition comes in. Essentially percent composition is part over whole x100. The part we want is carbon and that is 24.0g and we know our whole is 30g. 24/30=0.8 and you multiply that times 100 and get 80. We now know that ethane is 80% carbon. Pretty easy right?