The periodic table is a much more interesting concept than people give it credit for. Periodic means the repeating according to some pattern. The first periodic table is very different from the modern one. They are both very interestingly organized. The periodic table has the elements on them. The first periodic table was first introduced to us in 1869 by a Russian scientist named Dmitri Mendeleev. Mendeleev studied chemistry at the University of St. Petersburg. Mendeleev’s table had many differences from the one we use today. His periodic table was in order by atomic mass. Our modern one is in order by atomic number. His also only had about 63 elements. Our modern one has 118 elements. Although there are some differences, there are also some similarities. Both …show more content…
Halogens are group 17. Halogens are highly reactive in elemental form. Even though this group only needs one electron in its outer level, it has seven electrons. When halogens are in gas form they are diatomic molecules. Diatomic molecules are two atoms in the same covalent bonds. Halogens have many different uses. Bromine, Chlorine, and Iodine are three main halogens. Bromine is the only liquid metal that is a halogen. Chlorine is the most abundant halogen. Iodine is a shiny, purple-gray solid. All three of these elements are abstracted from salt-water. Iodine is important for the human body’s diet for production of the hormones thyroxin and to prevent goiter. Goiter is the enlarging of the thyroid gland in the neck. When Iodine is heated, it turns into a purple liquid. Hydrogen is the only elements that aren’t really classified as a group. Hydrogen is at the top of the periodic table because it is the lightest element. 90% of atoms are hydrogen. Most hydrogen is in water. When hydrogen is burned in oxygen, it forms H2O. Hydrogen has a single electron and is highly reactive. Hydrogen can also gain an electron when added to an Alkali Metal or an Alkaline Earth
Metal cations can be identified based on the colors they emitted off when heated in a flame.1 When atoms of the ions that were tested are excited, their electrons move up to higher levels of energy.2 When the electrons relax and return to the original states, they emit photons of specific energy creating wavelengths of light that produces colors.3 The test wire and Bunsen Burner were used to excite the solution in the crucible. The standard metal cations that were tested and their outcomes are as shown in Table 1.
Ancient scientist like Democritus and Leucippus proposed the idea of the atom(Doc.1). They were the first to start the long train of ideas and knowledge that brought us to the view of the modern atom(O.I). Since then, scientist such as John Dalton and Dmitri Mendeleyev have made huge leaps in the field of atomic science. John Dalton published the atomic theory of matter(Doc.1). Dmitri Mendeleev created the periodic table that modern scientist use daily(Doc.1).
Copper is also a very important element in the medical field. Also, the united states penny was originally made from pure copper. Finally, the Statue of Liberty did not always look green. Copper was the first element manipulated by humans. It is now, currently still a major metal industry.
Minerals 1. The minerals under the DRI for my age group would be calcium, potassium, sodium, copper ,iron, magnesium, phosphorous, selenium, and zinc. The mineral that comes below the DRI would be be potassium. However, it is not more than 80% below the DRI. However I did have a low potassium intake.
The periodic table is a basic concept of chemistry used to list and group elements. In a periodic table, chemical elements are arranged horizontally by increasing atomic number and vertically according to their chemical property similarities. No two elements are the same. Each element is unique. The Periodics as described by Isdell represent the elements of the periodic table.
A world called Pluton, where there is gender discrimination and females are superior to the males. Growing the population is Pluton’s main purpose. Herein, having the ability to give birth is power, thus females are dominant creatures as they are created with a womb which is able to carry an infant for thirty-six weeks. The only ‘capability’ that men have is the ability of passing the sperm on to the female to bore a child. The superiority of the female is felt strongly at the workplace, home and community at large.
(“Facts About Lead”) On the periodic table I am in column 14 and row 6. My atomic number is 82. When I stepped on the scale the other day my atomic weight was 207.2. My family is the Carbon group and I am classified as a metal.
We have more ways to learn about new elements and how to organize them. The modern system of organization by atomic mass it better than atomic weight because atomic mass is used more and portrays more trends. I think it 's crazy that the way Mendeleev found out to organize the table was solitaire. Mendeleev’s table was really close to being perfect, because his predictions were almost the same as the modern day periodic table. In Mendeleev 's table, grouped with the same chemical properties were put into the same column.
Neolithic vs Paleolithic Introduction: The Neolithic and Paleolithic arrive from the stone age period they are two separate time period each sharing some aspects from the other and varying from each other. The Paleolithic is a prehistoric period of human history and stand for “old stone age. This time period cover most of its primary tools and and cave paintings. The Neolithic stand for “new stone age” the develop more in craft/technology and basic aspect of live. They can be compare and contrast in various ways but it was the Paleolithic the paved the way for the neolithic era.
These were some major technological changes and advances in tools between the Neolithic and Paleolithic Era. The final major aspect that things had drastically changed was religiously. During the Neolithic
The Stone age consisted of the Paleolithic and Neolithic periods. The shift from the Paleolithic period to the Neolithic period is known as the Neolithic Revolution. Prior to the Revolution, people were hunter-gatherers
Tools and technology changed a lot in-between the two ages but some things stayed the
Dalton was best known for his work in the development of modern atomic theory. The was Dmitri organized the table was that he wrote out the elements on a card, each card has the atomic weights and were set in columns by order of the atomic weight. Each
He also created the terms “catalyst”; a substance that increases the rate of a chemical reaction, “isomer”; molecules with the same chemical formula as other molecules, and “allotropy”; the property that some elements have that allow them to exist in two different forms Dmitri Mendeleev, a Russian Chemist: 1834-1907, he formulated the period table, which he then used to predict the properties of 8 elements yet to be discovered. He also used his version of the periodic table to correct some properties of existing elements Joseph John Thomson, an English Physicist: 1856-1940, researched the cathode ray; streams of electrons observed in vacuum tubes, which led him into discovering the
The Stone Age is known to be the first prehistoric human culture defined by the use of stone tools. It is divided by 3 separate periods, the Paleolithic period, Mesolithic period, and the Neolithic period, the origin of the stone age coincides with the discovery of the oldest stone tools, which had been dated 3.3 million years ago. It went on until the time of smelting. Smelting allowed people to create tools, made from metal and stone. Most of the tools that were made, were created to help humans survive.