Lesson 21 and 22

Today we learned about neutralization, which is when a strong base and a strong acid react and form ionic salt and water. This is usually a double exchange of cations. We also learned that when two compounds have the same volumes and the same molarity they have the same number of moles. When this happens it means there are the same number of moles of Hydrogen and hydroxide so the substance is neutral.

Lesson 22

Titration is the neutralization process between a strong acid and base. When a strong acid is mixed with a weak base there isn't enough OH- ions to neutralize all of the H+ ions so the solution will not be neutral. It will however, be closer to 7 than either starting solution.



Practice Problems
4 is for lesson 21 and number 5 is for lesson 22

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Lesson 20

Today we talked about dilution. When you dilute something you make it either less basic or less acidic. 7 is the neutral number in the pH scale and by diluting a solution you can approach 7 but you can't turn an acid into a base and visa versa by dilution. We also learned that between each number on the pH scale there is a 10 fold. So 6 is 10 times more acidic than 7 and 5 is 100 times more acidic than 7 and so on.

 

Practice Problems

1. How much more basic is 9 than 7?

100 times more basic

 

2. To get a pH of 10 how much would you have to dilute 0.010 M of NaOH?

With 99 mL or water and 1 mL of the NaOH solution

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Disappearing Spoon:Chapters 10-12

Almost forgot this blog, hooray for random memories!
Chapter ten talks about medicine and it's connection to the periodic table. Silver was used to keep milk fresh and sterilize plates. Copper is used in things like doorknobs and railings because it has antiseptic properties. When bacteria touches the copper molecules it goes into to a self cleaning mode basically and eventually ends up killing the virus or bacteria. The element Gadolinium has been used to help kill tumors in processes such as radiation. Scientists have discovered that the best and most effective sperimicide is Vanadium.Granted some of these procedures have harmful side effects but nowadays what medicine doesn't? Kean then goes and talks about handedness or the qualities of proteins. The proteins in humans say that most people should be left handed. This obviously isn't true but it's kind of interesting how body compostition can be wrong. The handedness theory was brought to the table by Louis Pasteur when he was looking into lightbending properties. The next interesting scientist was Gerhard Domagk, who performed experiments on his own daughter! (What?! Why would you put your children in immediate danger?) She had a nasty infection from a needle puncture wound. I guess he was given a hard decision, using his drug and possibly killing her, or not using it and the girl losing her arm and or life. he took this chance and it ended up saving her life! After this miracle the drug prontosil went under inspection. Wat happened was a derivative of it, called sulfonamide. This produces folic acid and is more or less bacterial birth control.
Titianium is the only element that can be used safely and effectively in the body. It fuses to the bone and acts as a bridge between bones if need be. It's commonly used for things like hip replacements in the body. Continuing with the human body trend, iodine is used to fight birth defects. After this discovery the West tried to make it mandatory to put iodine in all salt, but India was not happy. Mahatma Gandhi led a march against iodizing salt but sadly for him it was unsuccessful.Today many Indian people still don' use iodized salt because it's too expensive or they are simply not exposed to it.
Then the topic moved from medicine to politics. Marie Curie was unable to get a proper science education because she was a girl so her dad homeschooled her. I guess the boys academy missed out because she went on to win a Nobel Prize with her husband and another on her own after that. Their studies focused on radioactivity as did their daughter Irene's. Sadly, she died at a relatively young age due to all of her exposure to radiation.

Disappearing Spoon: Chapters 8 and 9

Chapter 8 was about technetium, neptunium, and phosphate while also focusing on competition and mistakes. There have been many large mistakes in the scientific community throughout the ages.  Scientists, Linus Pauling and Emilio Segre have some of the largest mistakes for their time. Kean gives some examples of mistakes, like element 43 being discovered many times but that wasn't really the point of the story so I found it boring. But here are the mistakes and problems caused by Pauling and Segre. A scientist at Berkeley named Ernest Lawrence was working when Segrè was fired. Segrè had been working under  Enrico Fermi, who discovered element 93 by shooting uranium samples with neutrons. Edwin McMillan believed that element 93 would act like technetium, and asked Segrè to help him identify the element and its location on the table. After lots of studying McMillan and Serge found the element to be neptunium and was a cousin of rare earths. That means it branches off of the main periodic table. The other mistake man, Pauling, thought he was the one able to crack the code of DNA. Building from innacurate data of other scientists, Pauling made many wrong assumptions about DNA. Some of the inaccuracies stemed from the fact that he was using dead DNA instead of live DNA, which acts differently. He then wrote a paper about his discoveries, and the paper sound its way to Watson and Crick. These two were flabergasted becuase they had created a similiar model before but realized they were wrong and threw it out before sharing with the rest of the scientific community.

Chapter nine talked about toxins. (Oh look! A connection to our class and unit) Biology is more delicate than chemistry because living organisms count on strong amino acid chains. There is a section of the table that has all of the very toxic substances together. One example is Cadmium. This was dumped into the rivers of Japan purposfully, until it was discovered how harmful this substance is. Cadmium made the farmers weak with a disease that kind of reminded me of osteoporosis. It made the people have very weak bones from moving calcium out of the bone and replaacing it with zinc. But the most deadliest element is Thallium. This element because it unravels the amino acid chains in protein and doesn't bond to anything. Graham Fredrick Young experimented with thallium on his family. For obvious reasons he was sent to a mental hospital. But somehow he managed to poison seven other people.  These elements are related because they are around for a long time. Then it talks about Bismuth which is the heaviest element and emits yellow fumes. It expands when frozen and is commonly used in paints and dyes. Bismuth helped scientists study the structure of radioactive matter. Scientists think because of the half life they estimated at twenty billion billion years, Bismuth will live long enough to be the last element to go extinct. After bismuth is polonium, an element that makes people’s hair fall out. Then is radon, which is colorless and odorless and reacts with nothing. It seems like it would be a bogus, unharmful element then right? Wrong. It displaces air, which then sinks into the lungs and discharges radioactive particles that cause lung cancer. Not so harmless after all. The last part of the chapter talks about a teenage boy from Detroit who made a nuclear reactor in his back yard. In a rage after being informed of her son's arrest for stealing car parts his mother throws everything out of the shed where he was working. All of this was covered in radioactive material. Later after joing the Navy this boy is arrested for stealing smoke alarms. It turns out smoke alarms contain radioactive particles to help find smoke. The boy was trying to enhance his smoke dector in his back yard all those years ago. Personally this book is starting to terrify me about the world we live in. Smoke dectors have radioactive particles,what's next? Food?

Lesson 17-19

Lesson 17

In lesson 17 we learned that an indicator is molecular substance that changes color when it comes into contact with an acid or a base.

Acids and bases are corrosive. When pH is 7 it is neutral or pure water. Below 7 is an acid and above 7 is a base. This is a picture of the pH scale.

These pH solutions are classified by their colors you can observe. Acids and bases change the color of indicators.

.

Practice Problem

3. It means that the substance is neutral. 

Lesson 18

In lesson 18 we learned about cabbage juice and its indicator colors. Cabbage Juice: Pink=acidic, Green=basic, Purple=neutral. Substances that add H+ (just one proton) to a solution are acids. Bases are substances that add OH- to a solution. Substances that don't add H+ or OH- to the solution are neutral.

The definitions of acids and bases has changed over time.

• Arrhenius Definition: An acid is any substance that adds hydrogen ion to solution. A base is any substance that adds hydroxide ion to a solution.
• Brønsted-Lowry Definition- An acid is a proton donor. A base is a proton acceptor.

The products of a reaction is always called a conjugate.

(Red) Base + Acid --> Conjugate Acid + Conjugate Base

(Purple) Acid + Base --> Conjugate Acid + Conjugate Base

Strong acids and strong bases dissociate completely into ions, while weak acids do not.

Practice Problem
1. A base is a substance that adds a OH- ion to a substance and an acid is a substance that adds a H+ ion to a substance. 

Lesson 19

Lesson 19 talked more about the pH scale. The pH scale is a logarithmic scale the describes the concentration of H+ ions. pH is related to H+ by the formula: pH=-log[H+] Water dissociates into H+ and OH- ions. Below is a picture of the pH scale and examples of substances that fit into each pH level.

[H+][OH-]=1.0x10^-14

Practice Problem
3A. 4
3B. 12

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Disappearing Spoon Chapters 5-7

These couple chapters focused on war and how warfare effected the periodic table. The first part focused on nitrogen and the attempts made to capture it. Fritz Haber was the scientist who finally achieve this goal. He was trying to create nitrogen bombs to use in WWI, even though this was illegal in the eyes of  the Hague Convention, but his findings ended up going into fertilizers instead. Eventually Haber's research helped save lives by rescuing those who were starving but he also killed a fair number with his bombs. The next part talked about Colorado! (Hooray a connection to life!) On Bartlett Mountain in Colorado, molybdenum was discovered. This is used to strengthen steel and because it could withstand extreme temperatures in was incredibly valuable to the war effort. In a bidding war over the right to this mountain Otis King won and became insanely wealthy by selling the molybdenum to Germany. That was the most exciting part for me because of the Colorado connection. WWI wasn't the only war where chemical warfare was used though. In the Republic of Congo, war broke out after the discovery of large deposits of  tantalum were discovered. This is a metal used in making cell phones in the 90s. The Congo government was so unstable that tibes fought for the money being made by selling the tantalum to huge cell phone companies. In this war about 5 million people died. Later on in the book it talked about Henry Moseley who managed to discover 4 elements before his early death. He did this by creating an electron gun that could find new elements in other elements essentially. When Moseley died scientists began using more math and calculations to find elements.Next the book moved into the Manhattan Project.  The US was trying to perform nuclear warfare by manipulating plutonium and uranium. Not enough would burn out and too much would cause mayhem. This period of time is also where women were brought in to the science world. The wives of scientists who worked on the Manhattan Project would tire through hours of calculations and ended up as an enormous help. Yay women! Then some other large chemical warfare discoveries were made from Berkley. Both berkelium and californium were discovered there and many experiments on alpha and beta particles took place. The research there was competing with Russia to the point where Joseph Stalin was interested in the research to benefit him and the Soviet Union in WWII but failed. I still am not a large fan of this book but there are some little details that i find interesting.

Lesson 16

Lesson 16
In this lesson we basically used all the knowledge we've gained from throughout the chapter to solve problems. We also did an activity where we had to try and figure out which solutions werer which by weighing them and accounting for the molar mass. The rest of our activity involved doing problems.

Practice Problem
2. There is more solute in the container.
7. The NaBr  would weigh the most because it has more solute than NaOH. The KCl weighs  half as much as the other two because, 500 mL is less than 1 L or 1000 mL.

Lesson 15

Lesson 15
The biggest thing we learned in lesson 15 was that you can use a hydrometer to test the molarity of the substance. I really don't think there was much else so there is a practice problem below!

Practice Problem

 









 

 



Lesson 13 and 14

Lesson 13

A solute is a substance dissolved in a solution. A solvent is the substance in which a solute dissolves. A saturated solution is a solution that contains the max amount of a solute for a given amount of solvent. Molecules move from areas of high concentration to areas of lower concentrations. We also learned about molarity. The equation used to find molarity is pictured below.

 

Practice Problem

 

8. B

 

Lesson 14

In lesson 14 we put our knowledge from the previous lesson into practice. We also learned that concentration does not depend on the density of size of a sample. When dealing with ionic compounds, take all the ions in the equation into account. We also learned that volume is always expressed in liters for the equation.

Practice Problem

 

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Disappearing Spoon-Chapters 3 and 4

Chapter three talks mostly about the formation of the periodic table. Who organized it, the different attempts to organize it and all who were involved. Dmitiri Mendeleev is the man given credit for the periodic table. He was able to draft a table and predict where new element would be when they were eventually discovered. However, Mendeleev couldn't have done it alone. The work of Bunsen and Lecoq de Boisbaudran helped immensly. Boisbaudean brought in the idea of gallium and then rethought his predictions afterbeing corrected by Mendeleev. This chapter also talked about the formation of lanthanides. A teen named Johann Friedrich Böttger convinced a crowd he could turn silver into gold and was promptly arrested for alchemy by the king. The king asked him to turn silver into gold for him however, Johann knew he couldn't because his joke with the crowd was fake but he somehow managed to convince the king to pair him with a porcelain maker. While the pair mined for the rok used to make porcelain they discovered copious amounts of a large, unidentified rock. Later on a geochemist was able to indiviually indentify these rocks, six of them became lanthanides. Chapter 4 was all about the elements in space. The topics included the formation of the earth's crust, information about Jupiter and possible theories about why dinosaurs went extinct. A popular theory is that stars heat hydrogen in their cores and fuse it with other hydrogen atoms, making helium. Then helium fuses with helium. This cycle repeats until iron is formed. Jupiter has been deemed a failed star instead of a planet and so many elements have strange affects there. Father and son Luis and Walter Alvarez began studying a limestone deposit which is dated back to when the dinosaurs are thought to have become extinct. What they learned is that basically when a large meteor hit the earth, very large amounts of iridium-rich dust would have arose. This dust would've blocked out sunlight and kept life from surviving. This chapter also talked about dating the earth but it was incredibly boring.

Lesson 12

In lesson 12 we learned that aspartame is much sweeter than fructose. The smaller the LD50 the more toxic it is. LD50 values are of limited use in determining the long term effects of a substance. Even if you don't reach the actual LD50 there could be very serious long term effects that are not accounted for in the LD50.

Practice Problem

The molar mass of C8H11NO3 s 169g.

 

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