The discoveries of gallium (1875) and germanium (1886) provided great support for Mendeleev’s work. But Mendeleev went one step further than Meyer: He used his table to predict the existence of elements that would have the properties similar to aluminum and silicon, but were yet unknown. Both published tables with the elements arranged according to increasing atomic mass. Fluorine (F), chlorine (Cl), bromine (Br), and iodine (I) also exhibit similar properties to each other, but these properties are drastically different from those of any of the elements above.ĭimitri Mendeleev in Russia (1869) and Lothar Meyer in Germany (1870) independently recognized that there was a periodic relationship among the properties of the elements known at that time. For example: Li, Na, and K are much more reactive than are Ca, Sr, and Ba Li, Na, and K form compounds with oxygen in a ratio of two of their atoms to one oxygen atom, whereas Ca, Sr, and Ba form compounds with one of their atoms to one oxygen atom. However, the specific properties of these two groupings are notably different from each other. A second grouping includes calcium (Ca), strontium (Sr), and barium (Ba), which also are shiny, good conductors of heat and electricity, and have chemical properties in common. One such grouping includes lithium (Li), sodium (Na), and potassium (K): These elements all are shiny, conduct heat and electricity well, and have similar chemical properties. Identify metals, nonmetals, and metalloids by their properties and/or location on the periodic tableĪs early chemists worked to purify ores and discovered more elements, they realized that various elements could be grouped together by their similar chemical behaviors. ![]() Predict the general properties of elements based on their location within the periodic table.State the periodic law and explain the organization of elements in the periodic table.It may also be produced by the thermal decomposition of sodium azide. ![]() Pure sodium may be obtained by electrolysis of molten sodium chloride. Sodium was first commercially produced by thermal reduction of sodium carbonate with carbon at 1,100 degrees Celcius, in the Deville process.The most common sodium mineral is halite or sodium chloride salt. Although it's too reactive to occur in pure elemental form, it is found in many minerals, including halite, cryolite, soda niter, zeolite, amphibole, and sodalite.It is the sixth most abundant element on Earth, comprising about 2.6% of the earth's crust. It's found in the sun and many other stars. The symbol for sodium is Na, which comes from the Latin natrium or Arabic natrun or a similar-sounding Egyptian word, all referring to soda or sodium carbonate.There is only one stable isotope of sodium: 23Na.Sodium and its compounds are used for food preservation, for cooling nuclear reactors, in sodium vapor lamps, for purifying and refining other elements and compounds, and as a desiccant. ![]() In humans, sodium is important for maintaining fluid balance in the cells and throughout the body, while the electric potential maintained by sodium ions is critical for nerve function.
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