Barium Facts - Periodic Table of the Elements

Barium Facts - Periodic Table of the Elements Atomic Number 56 Symbol Ba Atomic Weight 137.327 Discovery Sir Humphrey Davy 1808 (England) Electron Configuration [Xe] 6s2 Word Origin Greek barys, heavy or dense Isotopes Natural barium is a mixture of seven stable isotopes. Thirteen radioactive isotopes are known to exist. Properties Barium has a melting point of 725Â °C, a boiling point of 1640Â °C, and a specific gravity of 3.5 (20Â °C), with a valence of 2. Barium is a soft metallic element. In its pure form, it is silvery white. The metal oxidizes readily and should be stored under petroleum or other oxygen-free liquids. Barium decomposes in water or alcohol. Impure barium sulfide phosphoresces following exposure to light. All barium compounds that are soluble in water or acid are poisonous. Uses Barium is used as a getter in vacuum tubes. Its compounds are used in pigments, paints, glassmaking, as weighting compounds, in the manufacture of rubber, in rat poison, and in pyrotechnics. Sources Barium is only found combined with other elements, primarily in barite or heavy spar (sulfate) and witherite (carbonate). The element is prepared by the electrolysis of its chloride. Element Classification Alkaline-earth Metal Density (g/cc) 3.5 Melting Point (K) 1002 Boiling Point (K) 1910 Appearance soft, slightly malleable, silver-white metal Atomic Radius (pm) 222 Atomic Volume (cc/mol) 39.0 Covalent Radius (pm) 198 Ionic Radius 134 (2e) Specific Heat (20Â °C J/g mol) 0.192 Fusion Heat (kJ/mol) 7.66 Evaporation Heat (kJ/mol) 142.0 Pauling Negativity Number 0.89 First Ionizing Energy (kJ/mol) 502.5 Oxidation States 2 Lattice Structure Body-Centered Cubic Lattice Constant (Ã…) 5.020 References: Los Alamos National Laboratory (2001), Crescent Chemical Company (2001), Langes Handbook of Chemistry (1952), CRC Handbook of Chemistry Physics (18th Ed.)

My Grandpa essays

My Grandpa essays I am now 15 almost 16 and I can recall being much of a different person a few years ago. Life a few years ago sure was better. Everything used to run smoother and people were rarely sad, but that was when I had my grandpa, he was a good man and a pastor at that. Everyone loved him; he was always there to cheer up people and to give advice to them. I remember going to church veer Sunday, not only to hear about God and all of that, but because my grandpa and my grandma went. Grandma was always with him where ever he went; they were like one; they loved each other so dearly. I remember that my grandpa really wanted to be an evangelist, so that he could travel and preach the word (the Bible) to others, but he always seemed to get stuck to churches for long periods of time. All the churches loved to hear him preach because my grandpa was a whole hearted Christian and believed in what he was saying! I can also remember fun days with him and of course my grandma. One day we all went to Lake Tahoe to go fishing, I was a little girl and I sure wasn't the best fisher. I was such a clumsy fisher that I had accidentally caught my grandpa on his shirt twice; boy-o-boy was that a funny day. My grandpa was the light of my family, when he was around the mood of the house seemed to be more cheerful and more alive. To me my grandpa was invulnerable and nothing could ever happen to him, but I guess that I was wrong. I remember when the happiness of the house was starting to fade because my grandpa was sick. We all thought that he had an ordinary flu or something, but since my grandpa was a hard head and never wanted to go to the doctor we didn't know for sure. One day he just couldnt take it any more, so he went to the hospital. Me I didn't take it as a big deal until we all went up there to see him. I went into his room thinking that he just had some little sickness or something, but then I say him laying there motionless with...