For centuries upon centuries, humans have developed ideas based on their experimental findings. Due to the fluidity of science, these ideas have been through many stages before the most plausible one is decided upon. Atomic theory began with Greek philosophers in Ancient times and carried over to modern science. The knowledge acquired by past scientists has had a great impact on discoveries made by those that followed. Furthermore, the models of the atom that Ernest Rutherford and J.J. Thomson proposed have definitely enhanced my Bohr model. Thomson’s “plum pudding model” was a pivotal pre-requisite to many updated models of the atom, for it incorporated the, recently discovered, electron. This only preceded Rutherford’s more accurate model, which conveyed that these electrons had a specific location relative to the rest of the atom. In my Bohr model, it is depicted that these very subatomic particles follow a specific circular orbit and can shift its path depending on the present conditions. Though the location and presence of the electron varies between models, all versions of it have information that holds true throughout. Aside from the negatively charged region to which the electrons belonged, the other major part of the atom is positively charged. J.J. Thomson’s model recognized most of the atom as positively charged with the occasional electron to balance the charge out. As a result of Rutherford’s gold-foil experiment, his model isolated the positive charge in a region unique to that of the electrons. The positively charged region was thus coined the “nucleus” of an atom, which was featured as the central point of my atomic model. This even further proves the point that each model of the atom supplies information for their subsequent relatives. Some may say that the models of the atom only replace each other, but this is not true. Every model leading up to the next
Chem 100 Research Project: Essay Outline
Lasers & Medicine
A. Definitions of Lasers and Medicine
1. Laser is a device that emits light through a process of optical amplification
based on the stimulated emission of electromagnetic radiation.
2. Medicine is the applied science or practice of the diagnosis, treatment, and
prevention of disease.
B. How they relate?
1. Cure diseases, surgeries, etc.
Traditional deffintion of organic chemistry Chemistry of compounds found in living species (organisms) Modern deffiniton of organic chemistry Study of carbon compounds (just because it contains carbon doesn’t make in organic
Torbern Bergman (1770) expressed the difference between organic and inorganic
(living v. nonliving) Antoine Lavoisier (1780’s) first table of elements, organic always contains C, usually H, often O & N
Michel Chevreal (1816) converted one organic compound into another then…
2. Uranium-237 + Helium-4 → plutonium-241
Plutonium-241 + electron → Americium-241
Americium is made by bombarding uranium or plutonium with neutrons in nuclear reactors
3. Americium is used in smoke alarms where it emits alpha particles and low energy gamma rays to form Neptunium – 237
4. When no smoke is present, the alpha particles ionise nitrogen and oxygen in the air in the detector…
February 16, 2015
Step 1. Converting copper metal to copper nitrate.
1. Cut and weigh of copper wire until approximately 0.5g.
2. Record mass.
3. Place in a clean, dry 250 mL Erlenmeyer flask.
4. Measure 4-5 mL of concentrated nitric acid in a graduated cylinder.
5. In a fume hood, add the acid to the copper until it dissolves.
6. Swirl contents to dissolve copper.
7. If after 5 minutes it hasn't dissolved, gently warm on a hot plate or add 1-2 mL of nitric acid.
8. Swirl until…
In September of 2011, Hillary Clinton delivered a speech on women and the economy at the APEC Summit in San Francisco; she discusses the importance to provide equal opportunities to women in the Asia Pacific. This topic can be tied to the concepts of orientalism, critical cartography, and “othering”. Which will explain the making of the South East Asia region.
The purpose of her speech was to encourage countries in the Asia Pacific region to provide equal opportunities to women in the work environment…
Use the web to answer the following questions. Include links to your resources for each answer. Once you have answered the questions upload the document to the appropriate assignment on School Loop.
1. What is environmental chemistry?
Environmental chemistry is the study of chemical processes occurring in the environment which are impacted by humankind's activities.
2. What are some questions that environmental chemists try to answer?…
THE MOLAR VOLUME OF HYDROGEN:
THE REACTION OF MAGNESIUM WITH HYDROCHLORIC ACID
• The molar volume of hydrogen gas will be determined by experimentally measuring the
of hydrogen evolved during the reaction of magnesium with hydrochloric acid.
• The universal gas constant will be measured and class data will be combined for statistical data
Mg(s) + 2HCl(aq) → MgCl2(aq) + H2(g)
Laws and concepts…
titrations in part II and III. Once we determine that, we use it with the sets of titrations with NaOH. Both Marisa and I will equally do work for both parts I, II, and III.
Part I - Acid-Base Titrations with Chemical Indicators
We obtained a 24 chem well-plate, 40 mL of HCl, and 100 mL of NaOH.
We cleaned out a buret with the base, NaOH.
We then obtained three different indicators: Boomcreiol green, Methyl orange, and 1% Phenolphthalein.
Using the well-plate we sorted the indicators into 3…
3. 41 mL of HCl was added to 2.01 g of sodium benzoate solution and a thick solution formed with a white precipitate. After the pH of the solution reached 2, the solution with precipitate was separated by vacuum filtration and dried. After the first drying period the mass of the watch glass and solid was 27.50 g. After the second drying, the solid and watch glass weighed 27.38 g. A constant mass was reached after the second drying as the change in mass was 0.44% indicating…
I. Determining the Unknown Acid Sample Size
Identification code of unknown weak acid #5
Concentration of NaOH solution, M .0609M
Mass of weighing paper plus unknown acid,g .86 g
Mass of weighing paper,g .8 g
Final buret reading, mL 19.2 mL
Initial buret reading, mL 13.5 mL
III. Titrating the Unknown Acid
Determination. 1 Determination 2
Mass of weighing paper plus unknown acid, g .922g .90g
Mass of weighing paper, g .87…