Halogen

Chlorine is the second to lightest member of the halogen elements. It is in Group 17 (Group VIIA) and period 3 of the periodic table. The element symbol for Chlorine is Cl. Chlorine is a greenish yellow gas that is corrosive, toxic and can be irritating to the eyes and respiratory system. Chlorine is a nonmetal that has the atomic mass of 35.45 amu. It has a melting point of -100.98 degrees Celsius and a boing point of -34.6 degrees Celsius. However, at room temperature it is a gas. Chlorine…

example, if you take the elements Te (Tellurium) and I (Iodine) they would not be in the correct order according to atomic weight, Te and I would need to be reversed. If they were reversed, then Iodine would not be in the same column as the other halogens. This is the reason we now arrange the elements of the periodic table according to increasing atomic…

Demitri Mendeleeve was a Russian chemist who invented the first periodic table in 1869. The periodic table he made was very different from the modern day periodic table we know today. Henry Moseley updated Mendeleev's version of the periodic table in 1915. This is more like the periodic table that we know and use today. The only difference is that there has been many more elements added. Mendeleeve also had predicted a lot of the characteristics and properties of elements that would fill up…

These families, shown and labeled in figure 2, include alkali metals, alkaline earth metals, transition metals, non-metals, metalloids, halogen gases, noble gases, lanthanides (or rare earth metals), and actinides (or rare earth metals). The first family includes group 1 on the periodic table. These metals are extremely reactive as they have 1 electron in their outer orbits. Hydrogen is included…

The element was assigned to group 17 (the halogens) because it’s color is yellow, similar to those of the other elements in the group. Also, the other elements have negative melting points and poor conductivity, the same as Fluorine. “The halogens have a wide range of physical properties” (127). In addition, we observed that “Fluorine and chlorine are gases” (127). Fluorine could not be placed…

550 dollars on energy every year. Some ways to help conserve energy can be checking for the ENERGY STAR-rating which is better for your wallet by saving you around $165 in its products lifetime. Using incandescent light bulbs with energy-efficient halogens, CFLs or even LEDs can save up to 30-80% on your energy bills. Even the small things can save energy such as washing your clothes in cold water instead of hot. By saving energy we save precious natural resources that our children's children…

Prions, endospores, and mycobacterium all are extremely resistant to antimicrobial treatment. Prions are extremely small, even smaller than viruses. Heat or formaldehyde aren’t very effective against prions. Endospores are extremely resistant to harsh conditions as well. They can survive heat up to 100 degrees C, drying, radiation, and majority of chemicals. Mycobacterium are extremely resistant due to their waxy cell wall. This cell wall blocks many things from entering the bacteria, making it…

Halogens are a special group because it is the only group that contains a solid, liquid and gas at stp. Iodine is also located in Period 5 in the p-block of the periodic table. It has 7 valence electrons and has 5 shells. Iodine is solid nonmetal at STP…

Element project (Br) Whats bromine? bromine (Br) is a deep red, noxious liquid, and a member of the halogen elements, or Group 17 group vlla of the periodic table. It has an atomic number of 35. What you will soon find out by my paper is how it's used in everyday life, how it's produced and its physical properties. Bromine was discovered in 1826 by the French chemist Antoine-Jérôme Balard in the residues from the manufacture of sea salt at Montpellier. He liberated the element by passing…

Introduction Microbes are essential to everyday life. Going from the basic food we eat to biogeochemical cycles, if we didn 't have biogeochemical cycles we would no longer have any of the resources that we have now; for example, there is plenty of nitrogen in the atmosphere but it 's all not available until it has been fixed, and that is when the microbes come in and changes the nitrogen in a way that is usable. Humans come in contact with microbes every day there is never a time there are…