LAB 1-3 Separation of a Mixture [Due Wed 9/28]

Hey Everyone, from reading your blogs it looks like you are getting the idea for the general outline and purpose of what we are trying to accomplish with the blog. If there are some comments asking you to add to your blog or edit it, please make the changes, your grade will reflect it.

For this experiment you need to write the normal paragraph summary outlining what you did. After you do that you need to consider the following:

1. Compare the amounts of iron, sand and salt that you had initially in your mixture to the amounts that you recovered. Were they all equal? Propose a reason for each of them being different than expected. I won't accept reasons stating that you measured wrong or did math incorrectly. I am looking for problems with the experiment.

2. How could you have made your separation better? For example: if you had sand left in your iron what could you have done to get it out?

Write a conclusion paragraph explaining how what we did relates to what we are currently doing in class. If you have further questions, this would be the place to ask the questions and address what happened.

Enrichment: Do a little research and find out the steps that are used to manufacture and purify a chemical. The important process here is the purification, because it directly relates to what we are doing in class.

Lab 1-1 Green Stuff [Blog Due Friday 9/23]

Ok, now you have completed your first experiment and have had a little bit of a chance to think about it.

The purpose of the lab blog is to do the thought processing that goes along with the experiences that you had in the experiment.

Your blog post should be outlined as follows:

• A quick summary of the experiment, tell me what you did (a procedure) and what happened (your results). I am usually looking for roughly a paragraph here, you need to provide enough so that I can tell that you understood what you were doing.
• Answers to the lab questions, in this case they are:
• Explain how you can determine if a property of green stuff is a physical property, or a chemical property.
• Describe the different phases of matter of the chemicals (water is a chemical too) used in this experiment. Make sure to tell how solids, liquids and gases are different.

•  Describe how the material relates to what we have been completing in class. Also this is where you can pose questions that the lab made you think about, I like to see this stuff and respond to it.
• Enrichment Questions: I will at times pose enrichment questions, if you want to get 5/5 on all categories all the time, you will need to answer these. For this experiment, come up with an experiment that you would like to try with green stuff. Its name is copper (II) chloride if you want to do a search.

Lab 1-2 Indirect Measurment [Blog Due Monday 9/19]

First in your blog write a one paragraph summary of the experiment and your results.

Then: Answer these questions

1.     Some methods for finding the diameters and thickness are much better than others. Explain the limitations of using water displacement and a ruler to calculate the thickness.

 

2.     Suggest some sources of error in how you conducted the measurements that might explain any error in your diameter value. 

3.   Describe one problem you encountered in your experiment and tell how you overcame that problem. This could be related to question #2 above, or not.

To conclude your blog entry, explain how you could use a method like the one in your experiment to solve another problem that might not have a clear cut answer.

ENRICHMENT: 

As a person who will soon be paying your way through life, learning to evaluate the “best deal” is an important skill so you can get the most value for your money.  Obtain information about the price and amount of foil in roll of each type of aluminum foil.  Use this information, along with the thickness value for each type of foil, in order to determine which type of foil gives more value.  You may choose to do this by:

a)     showing a mathematical way of figuring this out, OR

b)    describing in writing how you would figure this out. 

Prices:     HD: $3.79 for a roll 70 cm X 6 m

               Regular: $5.79 for a roll 40 cm X 15 m

Welcome to 2011-2012 School Year!!

Dear Students,

I am excited about getting the new school year started. Here is a little about me…..

About Me:

I was born in Rochester and grew up in nearby Honeoye Falls. I graduated from HF-L and from there went to Nazareth College where I majored in chemistry. I graduated and went back for an extra semester in order to student teach. After student teaching I got a job in the Greece School District teaching 7^th grade science for the second half of the year (it wasn’t for me). After that I got hired here at Rush-Henrietta and now it will be my fifth year here!! I just finished my Master’s Degree at SUNY Brockport!! My next step is going to be to apply for doctorate programs and likely become a teacher of teachers.

Family and Stuff

Some of my family is still here in Rochester. My parents moved from Honeoye Falls to Palmyra where they both work, so they are still in town. My little sister just graduated from Nazareth College as a speech pathologist. She just got a job in Orlando, FL and lives down there, I helped her move. I have no pets, but part of me wants to put together an awesome tropical fish tank. My older brother lives in Washington DC and my best friend lives in LA, I miss them both.

Non-School Stuff

I am big time into soccer. I played soccer at HFL and Nazareth. I still play sometimes at TSE or the Sportsgarden, but I am now mainly a referee. I college professional, and summer league games. You can see me on the rhinos games sometimes. I travel a lot of refereeing, all across the northeast. In the winter I ski, I also try to get on my mountain bike whenever I can. I am not a huge gamer, but in my occasional free time you can find me on my PS3 (rewryn).

About this school year

I look forward to this school year and have some goals. The main one is for everyone to get a better understanding of Chemistry. I also want to make you guys better problem solvers. You will get better by thinking analytically and working hard. I also want to help my students get ready for college. If I am not totally forth coming with information, it is probably because I want you to do the thinking. I do want you to ask questions and as we get to know each other you feel like you can ask the tough ones when necessary. I wish everyone a safe an successful school year and look forward to working with you this year.

 

Sincerely,

Mr. Andrew Evangelos

Blog 11.1 Corrosion of Metals [Due Monday 5/23]

1.   a)   Was the penny wrapped in steel wool (made of iron) more or less corroded than

unwrapped penny?

b)     Is this protection from corrosion by using the “coating” technique, or the “sacrificial metal” technique?

c)      The Statue of Liberty was becoming so weak from the corrosion of the copper that it was shut down and “refurbished” in the early 1980’s.  In the process, many iron bands were added to the inside of the statue, making direct contact with the copper.  These bands are now regularly checked and replaced as needed.  Explain why this chemical trickery works to prevent the further oxidation of the copper statue, based on Table J!

My father wrapped the wooden posts on his porch in a product designed to protect the wood.   The product is made out of painted aluminum.  He used iron nails (non-galvanized ones) to nail the aluminum sheets to the wood.  Now after 2 years of weathering, the places where the nails penetrated the aluminum are corroding and crumbling. 

 2.  Explain why this corrosion is happening, in terms of the two metals and Table J.

 

3.  Explain why this problem could have been prevented if the spots where the nails were put in had been sealed with caulking.

3.  Answer the two “Lab Questions” from page 1 of this lab.

Enrichment:

Two metals in contact with each other and moisture will react in what is called a “galvanic reaction.” 

Metal A will be oxidized by the action of oxygen and with the help of the moisture. 

         

                   A (s)  +  O₂  --> The oxide of A^x+  

The Metal B will be oxidized as well, but this happens as it tries to restore electrons to the first metal.

                  

                   B (s)  +  A^x+  --> A  +  B^y+

This process can be helpful (as in the case of a ship hull being protected) or destructive…

Based on the description of my father’s corrosion problem in the Conclusion section, decide with Metal is “A” and which is “B.”  Write the reactions shown above, using actual metals in place of A, A^x+, B and B^y+.  Make sure you pay attention to proper ion charges (Fe becomes Fe²⁺).

Blog 11.2 Table J and Metal Reactivity (Due Monday 5/16)

Blog Questions:

1.      The solutions you used were all nitrate solutions. For example, the silver ion solution (Ag¹⁺) is really a solution of silver nitrate (AgNO₃). The complete REDOX equation for the reaction between magnesium metal and silver solution is as follows:

         

              Mg_(s)    +    AgNO_3(aq)     -->    Mg(NO₃)_2(aq)   +    Ag_(s)

a) The nitrate ion is known as a “spectator ion”.  Explain why you think this name is appropriate:

b) In the reaction between magnesium and silver solution, what is oxidized

What is reduced?  

2. Propose a rule that predicts whether or not metal X and metal ion Y⁺² will react, based on Table J.

3.  Answer the two “lab questions” from page 1 of this lab:

1.    What is an “ACTIVity series” and how does it relate to what I already know about the behavior of metallic and non-metallic elements?

2.   How is an activity series used to predict (or explain) which metal (or non-metal) is more reACTIVE than another?

4. History of Metals

Currently there are 86 known metals. Before the 19th century only 24 of these metals had been discovered and, of these 24 metals, 12 were discovered in the 18th century. Therefore, from the discovery of the first metals, gold and copper, until the end of the 17th century, some 7700 years, and only 12 metals were known. Four of these metals, arsenic, antimony, zinc and bismuth, were discovered in the thirteenth and fourteenth centuries, while platinum was discovered in the 16th century. The other seven metals, known as the “Metals of Antiquity,” were the metals upon which civilization was based. The first 4 had been discovered and were in use before cultures had developed the ability to communicate in writing.  They are referred to in the oldest written documents we can find (like the book of Genesis in the Bible, as well as ancient Egyptian, Phoenician and Babylonian texts).  These seven metals were:

1.     Gold, 6,000 BC

2.     Copper, 4,200 BC

3.     Silver, 4,000 BC

4.     Lead, 3,500 BC

5.     Tin, 1,750 BC

6.     Iron, 1,500 BC

7.     Mercury, 750 BC

On Table J, the elements above H₂ are prone to oxidation in the air, and are therefore unlikely to be found in pure form on the Earth’s surface.  Rather, they are in compounds called “ores” which are metal oxides, like Fe₂O₃ (iron ore).  Why do you think gold, silver and copper were discovered so long ago by humans, but the other 4 metals were discovered later?

 

5.  https://www.e-education.psu.edu/files/matse081/animations/lesson04/u04_metalWork.html

A significant advance in human civilization occurred when humans discovered how to extract copper from copper ore.  When mixed with tin, the alloy is called bronze and is harder than either metal separately.  Go to this website.  Check out two things:

·         How copper was “smelted” in ancient times.

·         How bronze was made.

 

Enrichment:

Ag¹⁺ is a very important ion in the history of Rochester, since it was the primary ingredient in George Eastman’s black and white KODAK film industry.  Research how this ion is used in photography.

Lab 10.3: Titration and Colligative Properties (Due Wed 5/4)

Titration Section

In this part of the experiment you had to do a titration to determine the concentration of the base (NaOH). In the process of the titration you produced three separate pieces of data and calculated the deviation.

Describe how far apart your different measurements were. Did they vary a lot? Were you surprised in how much variation that you found. Can you think of any ways that your actions during the titration may have caused issues with your values? What could you have done to make your trials more consistent across the board?

Colligative Properties Section

In this section you were asked to investigate some real examples of the colligative property at work.

Antifreeze is used in engines as a coolant. They take advantage of both the freezing point depression and boiling point elevation. Come up with a reason why each of these are important based on the variable climate that we live in.

The reason these processes work is due to the attractions that take place between the solute molecules and the solvent molecules. Describe how the attractions cause the freezing point depression and how they also cause the boiling point elevation.

Enrichement:
 Find another application of the colligative properties. Find a real world use, some hints: One is used in the making of a tasty treat that we will actually do later in the year. Describe how the process works for the example that you find.