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<span>A chemical that will ignite spontaneously in air at a temperature of 130 degree fahrenheit (54.4 degree celsius) or below is identified by the term pyrophoric.
Pyrophoric substances are those that ignite spontaneously when in contact with air at 130 °F or below. Some substances that are pyrophoric include Iron Sulfur (FeS) or some metals like finely powdered Uranium. To handle pyrophoric substances, it is required to work in an inert atmosphere (i.e. an atmosphere without oxygen).
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Answer would be A)the atom
The entire mass of a black hole
