The element astatine has no uses currently, apart from basic scientific research. Astatine is very scarce in Earth's crust, and its various isotopes have short half-lives. This means that the total amount of astatine at any given time is less than 30 grams.
Astatine is formed by the decay of thorium and uranium, which means it is biologically toxic due to its radioactivity. Its name comes from the Greek word "astatos," which means "unstable." Astatine was first produced by Dale R Carson, K.R. MacKenzie and Emilio Segrè at the University of California in 1940. They used a machine called a cyclotron to bombard an isotope of bismuth (bismuth-209) with accelerated alpha particles. Two other groups came close to discovering astatine; Horia Hulubei and Yvette Cauchois attempted to analyze mineral samples using a high-resolution X-ray apparatus, and Walter Minder observed the radioactivity of radium and claimed it seemed to have another element present. Chemical tests suggested it was like iodine. Due to its scarcity, astatine is only produced when it is needed. The total amount of astatine that has been produced is 0.05 micrograms (0.00000005 grams). Through the use of a mass spectrometer, scientists have confirmed that astatine behaves chemically like other halogens, iodine in particular.Learn More
To calculate the mass number of a specific element, find the number of protons and the number of neutrons that element has. Then, add them together. A periodic table of elements is needed to complete this task.Full Answer >
The halogen with the least negative electron affinity is astatine, which has an electron affinity of -270 kilojoules per mole. The lower electron affinity is related to the larger atomic size of astatine. In larger atoms, electrons will not be as attracted to the nucleus.Full Answer >
The chemical equation for the neutralization of sulfuric acid and sodium hydroxide can be written as H2SO4 + 2NaOH —> 2H2O + 2NaSO4. The equation shows that sulfuric acid has an equivalent value of 2, which means that one molecule of H2SO4 can neutralize 2 molecules of a base, such as sodium hydroxide, which has an equivalent value of 1. The neutralization equation also represents one of the production processes that produces sodium sulfate, the sodium salt of sulfuric acid and is used to neutralize surplus sulfuric acid by sodium hydroxide during the making of rayon.Full Answer >
Nickel bromide is a chemical compound with the formula NiBr2. Its molar mass is 218.5 grams per mole, and its density is 5.098 grams per cubic centimeter. Its melting point is 1,765 degrees Fahrenheit, and its solubility in water is 134 grams per 100 milliliters at common temperature.Full Answer >