3 questions number 6

1. Recently i completed a worksheet on stoichiometry in chemistry 

2. Recently i have learned the most architecturally sound way to build a chicken coop

3. i hope to soon begin preparations for the ACT and attempt to achieve a 31 composite score

 

Explore: Solutions

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A solution is a solid (solute) dissolved in a liquid (solvent), and there are several different kinds of solutions, including electrolytes (salt solution) and non-electrolytes (sugar solution). We could tell the difference between the two using an electric conductivity tester, the electrolytes conducted electricity in solution, the non-electrolytes did not conduct in solution, and the DI water didn’t conduct electricity. This is because the electrolyte is an ionic compound which has been separated into the ions. Which give the water charge, while the non electrolyte didn’t have any ionic bonds, therefore no ions and no charge. One can diagram salt solution as the Na+ with the O in water facing/surrounding it, while the Cl- holds the water with the hydrogen facing it. One can diagram the sugar solution with the particles simply surrounded by water, no polar reaction

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Chemical Reactions

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Today, we performed many chemical reactions, with many different materials. my reaction was one of zinc and lead (II) nitrate, the balanced reaction for which was Zn + Pb(NO3)2 —> Pb + Zn(NO3)2. I could tell this was a chemical reaction because of the change in color, the production of gas as well as the production of a precipitant, my reaction held all 3 indicators. The reactions in each section were similar in the change in the reactants, and the products of a reaction, from 2 reactants to one product, and ect. for each section, one can create a model for the products and their quantities in a reaction, and use it to predict the products of a reaction. All because each type of reaction in a section yields similar products, because of the type of reaction that defines that section.

white powder and unknown liquid

In class, we experimented with amounts of powders and liquids and the amount of gas produced. we found that as we changed the amounts, we would see more gas produced (along the slope of the mass of powder over mass of gas in the balanced equation) up until a certain point. This change in production was brought about by limiting and excess reactants. limiting reactants are the reactants you control the amount of in an experiment, excess reactants are exactly that, excess. There is an unlimited amount of this reactant in the equations. The reactant in excess matters because you can use the amount taken by it to calculate many aspects of a reaction, including the amount of excess reactant.

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white powder and clear liquid

white powder and clear liquid

the solids produce roughly 50-75% of their mass in the reaction. most reactions we attempted had similar reproductions of the mass change, but most chemical reactions would have different rates of change. there is indeed a molar relationship, with the balanced equation and molar masses, one can determine the amount of gas produced by certain amounts of solid. (line of best fit)

3 questions 3/14/14

Recently, i have completed the review for the sba and the calculations for our mole lab.
Recently, i have learned the concept of the mole and its role in chemistry.
Next, i plan on furthering my knowledge of the mole and how to use it in calculation

beans in a pot

using beans, we learned more about relative masses and “pots.” A “pot” of beans is simply the amount of beans that make up the relative mass of an “element” in a group of “elements”. the relative mass is used because it shows the amount of pots in relation to the relative mass of the other beans. The pot is a model of a mole in the fact that it is a unit of amount of beans in a certain mass of beans, and a mole is a unit of amount of atoms in a certain amount of anything. they’re both simply units of quantity. the relative mass of carbon is used, because it is the most exact, one mol of carbon atoms is 12g of carbon 12.

how to: percent composition.

to find the percent composition of a certain component of a compound, one needs only to find the molar mass of said particular part of a compound and divide it by the total mass of the compound. for example; to find the percent composition of CO2, you need to find the molar mass of carbon, (12.01) and the molar mass of oxygen, (16.00). multiply the masses by number of atoms in the compound, (16.00×2) (12.01×1) and you can find the total mass (44.02) then divide the totla mass of oxygen in the compound by that number and you can find the percentage.  (32/44.01) the percentage of oxygen in CO2 is.7271, or rounded and put into percentage, 73%. empirical formulas are just the opposites of percent composition, it gives the percentages as givens, from there, you use molar masses to find the compound. you simply divide the mass of the component and divide it by the molar mass of the same component, from there, divide each of the products by the smallest product. This will give you the number of certain atoms in the compound. From there you can determine the empirical formula.

science by numbers

to be accurate, is to be close to the actual value of a given piece of information. and to be precise is to have multiple repeatable  measurements in range. these attributes are reinforced by the use of significant digits, allowing calculations to maintain similar precision throughout the process without integrating false variables in the equation. these numbers allow a greater understanding of the workings of chemistry. in the article, it says that several elements had their masses changed to be more accurate. these more accurate numbers are a part of science, the constant search for more accurate information through more precise calculation (in this case)