Disappearing Spoon Chapters 18 and 19:

Chapter 18 begins with talking about standards bureau, which is a science of measuring absolutely everything! Most countries have standard bureau. Then it talks about individual measurements. Then it talked about kilogram and the relationship between the measurement in general and what it effects. The kilogram is the last base unit bound to human strictures. Then it talked about more measurements, their standards, and what if effects. Then it talked about a K20 with flew to Paris and how the kilograms affect it. Then it began to talk about how the goal for every unit is to be able to email the definition to a colleague on another continent and for that colleague to be able to reproduce something with exact dimensions, according to England's bureau of national standards checklist. The problem with the kilogram is it continually shrinks or expands and that causes international worry and embarrassment. Then it talked about "leap second" and atomic clocks, and how this is not a good solution. In the 1960s, scientists adopted the cesium standard as the worlds official measurement of time. Then it continued with different types of measurements, and concluded with the idea about earth and space, and how we came to be as well as if we have any place in intruding space and the life that may or may not exist! Chapter 19 began with talking about the periodic table and Francium, along with the hope that "island of stability" is perhaps the answer to extending the table beyond its current limitations. Then it talked about the most common, 90% of particles in the universe being hydrogen, and the other 10% being helium, and the scarcest being astatine. Due to the immense difficulty it is to find astatine, the founding of it was a bit of cheating. Some radioactive elements may turn into astatine after going through alpha or beta decay. Then it began talking about the comparison between astatine and francium. When you get the nuclei the size of astatine and francium, the limited reach really catches up with the strong force and has difficulty binding all the protons and neutrons together. Then it talked about Goeppert-Mayer and developing the theory about long lived "magic" elements; atoms with two, eight, twenty, twenty eight, ect., protons or neutrons that were very stable! Then it went on about that magic elements, and stability in general. Then it began to talk about Einstein and how he spent his career trying to unify quantum mechanics and relativity into coherent and svelte "theory of everything", he semi failed however. Sometimes, when the two theories mesh, they greatly compliment each other. However, the speed of light, and relativity don't really fit well overall. Then it moved into the properties on the periodic table in general. Then it talked about how the periodic table is graphed into musical staffs and William Crookes who designed two fittingly fanciful periodic tables. Then it talked about both those tables, and concluded with how to read the table on all different levels, maybe they'll see something new, and that all human beings have managed to pack the periodic table of elements and the real admirations that coincide. Time to celebrate!!!!! Finalllyyyyyyyy done with this boring/sometimes interesting book!!!!!! Hope everyone had a good weekend.

 

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Unit 4 Review:

In unit 4, we started with toxins. Toxins can enter the body in a limited number of ways, also they can react with H2O in the body. Toxins may be molecular, ionic, or metallic substances. The definition of toxins are substances that interact with living organisms and cause harm. Something important to know is how to write an interpretation, NaVN(s) + HCL (aq) ----> NaCl (aq) + HCN (g) solid sodium cynics reacts with aqueous hydrochloric acid to produce aqueous sodium chloride and gaseous hydrogen cyanide. Then we moved on to equations, which allow you to track changes in matter on an atomic level. Also, a physical change is a change in a matter in which a substance changes form but not identity, and a chemical change is a change in matter that results in the the formation of a new substance or substances with new properties. Something important to know is that ionic compounds do not dissolve in the same way as molecular solids. The dissolving of ionic solids can be shown with a type of equation that stresses the formation of ions in solution. Very important!! If a gas is one of your products, the mass of the products will be less than the mass of the reactants unless you trap the gas. Then we moved on to balancing chemical equations which is an equation that shows the true mathematical relationship between the reactants and the products in a chemical reactant. When balancing equations, you can only change the coefficients. Coefficients in a chemical equation indicate how many "units" of an element or compound you have. Important! Combination: A + B--> AB, decomposition: AB-->A + B, single: A + BC--> AC + B, double: AB + CD ---> AD + CB. Then we moved into the chart again! A lethal dose is the amount of an ingested substance that kills 50% of test sample of animals, it is expressed in mg/ kg, or milligrams of substance per kilogram of body weight. We learned how to find the LD 50 or solve for it in the chart! Then we went into percent error, which is observed value - actual value times 100 / actual value. Chemists use the percent error to express how close their measurements are to the accepted value. Then we moved into scientific notation! Hopefully you all know how to find a mole! If not (learn it!!! Charts!). Then we talked about a solution which is a mixture of two substances that is uniform throughout. A solute is the substance dissolved in a solution. And a solvent is the substance in which the solute dissolves in a solution. Concentration refers to the amount of solute that is dissolved in a solution. Molarity is M= mole over liter. Very important!!! The relationship between the number of moles of particles in a solution is proportional. Then we moved into pH and acids and bases ect. An indicator is a molecular substance that changes color when it comes into contact with an acid or a base. Left side from 0 to 7 is an acid, and 7- 14 is a base. At 7 is neutral, water is a neutral substance. That is why you can dilute an acid or base with water. In order to find the pH of a substance it is -log (H+) H+ is the hydrogen concentration, and OH - is the hydroxide concentration. OH and H+ must equal 1.0 times 10 to the -14. There are two definitions for an acid and base. Starting with the Arrhenius, an acid is a solution which adds hydrogen to the solution, and a base adds hydroxide to the substance. And Bronsted-Lowry Definiton is an acid is a portion donor and a base is a proton acceptor. Each time the H+ concentration is diluted tenfold, the pH number goes up one unit. A strong acid and base, dissociate completely in a solution, and a weak acid and weak base don't dissociate completely in a solution. When strong acid and bases are mixed, the pH approaches 7, but never reaches it completely. Titration is a procedure in which a neutralization reaction is monitored with an indicator allowing you to calculate the unknown concentration of an acid or base. When the equivalence point is reached, the number of moles of H+ ions equals the number of OH- moles. Something important to know is that a precipitate is a solid produced in a chemical reaction between two solutions(chart). Lastly! We learned about stoichiometry! G-->mol, molar ratio, mol--> g. When doing a stoichiometry problem, the number with the lowest grams in the end is the limiting reactant. You can use the limiting reactant when finding the percent yield which is: actual decided by theoretical times one hundred. Good luck on the test! :) a few problems below!

 

 

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Lesson 26

Today we continued practicing what we learned yesterday, and it made way more sense! :) then we went even further with what were learning and put it all together. First, percent yield is actual yield divided by theoretical yield times 100. Also, we figured out how to find the limiting reactant and applying it to the question. Here's an example: CaCl2+NaCO3----> CaCO3+2NACl. First step is to figure out the chemical equation (if it isn't given) and balance it. Step two is finding the molar mass of all of them. Then apply stoichiometry. Grams -->mol, molar ratio, mol--> grams. Then after finding the limited reactant, that number is the theoretical yield. That is what we did today! And loooots of practice :) homework below!

Homework:

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Lesson 24 and 25:

Today we went over lessons 24 and 25 which closely correspond. Beginning with chapter 24, it is important you look at the coefficient to determine your molar ratio. The mole ratios are the proportions in which two substances (reactants, products, or both) combine or form. A mole ratio is the ratio represented by the coefficient in a chemical equation showing how many units of each substance must combine to make the maximum amount of products. When reactants are not combined in their exact mole ratios, one of the reactants runs out (limited reactant) and the other is left over (excess reactant). For example, N2 + 2H3---> 2NH3, the 2H3 will run out first because you need more of it to complete the equation. It is a 1:2 ratio. Lastly, when comparing any two things on a balanced equation, you HAVE to compare the moles <---- important!! Homework below (didn't make any sense!!)

In chapter 25, the main things to know is that in order to determine the mass of product produced by a certain mass of reactant, it is important to convert the mass to moles and then back to mass. Calculations involving mole ratios and masses of reactants and products, are referred to as gram-mole conversions, or stoichiometry calculations. Use the handy dandy chart to help! Go through the "mole tunnel" :) again super uber confusing homework below. Barely any of either chapter is filled out, because it makes no sense!!!!!!

Homework (confusing!!!!!!!!!!!):

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Lesson 23:)

Today we went over lesson 23. Vocab word!! Precipitation is a solid produced in a chemical reaction between two solutions. ( this is only the definition for the lab we did today). Also, the mixing of two ionic solutions sometimes results in the formation of a solid precipitate. Precipitation is not limited to solids, and the degree to which a compound dissolves in water is solubility. (Very important!) lastly! in order to figure out which compounds are soluble and which aren't, chart below! homework and chart below :)

Homework:

 

 

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Disappearing Spoon chapters 13 and 14:

In chapter 13, it began talking about how elements have had a close relationship with money. Then it began a story about a man named Midas who asked to turn everything he touched into gold. The story went more into depth, but this was the overall outcome. Then, it began talking about a professor and a few historians who wanted to test the theory of Midas touch being nothing more than zinc in the soil. By having a Midas-era furnace, they loaded local ores. Then they melted them, molded, and let it cool. It hardened into gold. Then, began the story about the city of gold, and gold rushes. A man named Hannan found a place where gold was everywhere. The rush came, and people began a frenzy trying to find gold. As more gold was found, resources price sky rocketed. As people were so desperate for water and food etc, a fight even took place. While they were digging, they were just throwing out rocks. Gold is aloof and doesn't mix inside minerals except one tellurium. This element bonds with gold to form minerals. One this was discovered, all hell broke loose! May 29, 1896. The generations after this group, learned their lesson not to throw rocks aside. Then, an ancient ruler established a real currency system by separating electrum into silver and gold coins. The story continued on about counterfeiting, in today's world and back then. Changing topics, the color of light depend on the relationship of starting and ending energy levels from electrons. It concluded with aluminum and a professor Jewett who worked on separating aluminum throughout his undergraduate years. Then, in 1886, Charles Hall ran an electric current from homemade batteries through a liquid and dissolved aluminum. The energy was quick and easy! He became widely famous. Lastly, he talked about the different spellings of aluminum! This chapter started off very interesting! I like when he tells more of a story then all chemistry ;) in chapter 14, it began talking about how to really advance in science, money had to be involved. Usually the higher class were the ones making inventions. Also, early on, it began more as a hobby than a profession (which I found interesting!). Then it talked about a man named Goethe, his theory or how colors worked relied as much on poetry as science. He made many contributions to science, and his last contribution was with a man named Donereiner. They spent a lot of time together. He inspired Strontium, and a doctor found it in a hospital lab. Later, Laszlo Moholy-Nagy drew a distinction between "forced obsolescence" and " artificial obsolescence". Then, ink was invented by Parker. Then he told a story about Mark Twain and the periodic table. Lastly, he talked about Lithium and how a man named Lowell responded to it. Lithium regulates proteins that control the body's inner clock. This chapter wasn't as interesting! But it was alright :) 3 weeks until Christmas break!!!! :)

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