Albina Contreras and Karla Santos Title: Interpreting the Periodic Table Date: 12-18-14 Subject: Honors Chemistry / Period 5 Introduction: The periodic table is a table of the chemical elements in which the elements are arranged by order of a atomic number. The periodic table also has a special name for its vertical columns. Each column is called a group. The elements in each group have the same number of electrons in the outer orbital. Those outer electrons are also called valence…
an atom is the proton. The proton is a very important part of an atom, because the atomic number of an atom is equivalent to the number of protons that that atom has. Additionally, the mass of an atom is equal to the sum of the number of protons and the number of neutrons of that atom. The number of electrons that an atom has is also equal to the number of protons that that atom has.…
This implies many things. The atomic number of an element indicates how many electrons and protons there are. The number of electrons should always be the same of protons because their charges cancel and the overall charge of the atom is neutral, and so the number of protons and electrons…
1869, a chemist named Dmitri Mendeleev and a German chemist named Lothar Meyer proposed a “periodic table of elements” on the base of periodic repetition of properties. In 1864, before Mendeleev, and John Newlands arranged the elements in order of atomic mass where every eight elements has similar properties. He called the relationship “the law of octaves”. Even so, this law could not be applied for the elements beyond Calcium, so it was not accepted by the scientific community. The modern…
The basis of Mendeleev’s periodic table was categorizing the elements according to their physical and chemical characteristics with regard to their atomic weights. Mendeleev was the first to come up with a structure for the periodic table with columns and rows. There were other scientists who have worked on tabulating information of the elements even before Mendeleev, however, he was the first scientist to come up with a periodic trend to predict the properties of elements which were not…
Chromium got this name because of the many different colors in the element. This element is hard, metallic and shiny. Chromium doesn't tarnish. Chromium is a metal element. Chromium's symbol is "Cr" and has an atomic number of 24. This metal is the first element in group 6. It has an Atomic mass of 52.0. Chromium has 4 known isotopes. Chromium is a "transitional metal." The other family members in period 6 are molybdenum (Mo), tungsten (W), and seaborgium (Sg). All elements in group 6 are…
Dmitri Ivanovich Mendeleyev, born on February 8, 1834, was believed to be the youngest of 14 children. His father, Ivan Pavlovich Mendeleyev was a teacher at a local gymnasium. Around the time Dmitri was born, his father went blind and later died in 1847. Consequently to support the family, his mother Mariya Dmitriyevna Kornileva began working at a small glass factory in a nearby town, and eventually started managing it. On December of 1848, the factory burned down, and the family moved to St.…
determined by the atomic number, not by the atomic weight. Mosely used a device known as an electron gun to fire streams of electrons at different elements. He found out that different elements give off different frequency of X-rays. Mosely calculated these frequencies and discovered that the frequency relating to atomic number gives off reasonable results, while frequencies of the atomic mass is unpromising. Not only he concluded that elements should be classified by its atomic number. He…
no sisters.John dalton lived and worked in England as a teacher and a public lecture.He wa very interested in meteorology for the longest.He published meteorological observations and essays which he recorded.He did so many things, he made his own atomic theory he was also was very interested in color blindness.His serious interest in this led him to the view of atomism. Between his life and death John Dalton made his living as a teacher and public lecturer.He began teaching at the age of 12 he…
Group 1 Elements Referring to the table created from observing the characteristics of the three elements from group 1, Lithium, Sodium, and Potassium, we can see that they all share the appearance of being lustrous and metallic, with a silvery-white presentation, and it is also known that they are all alkali metals. It is also noticed that they are all soft metals easily cut with a knife rather than most metals such as calcium or iron. All three elements are stored within oil, with Sodium as an…