Question

Which of the following element is an artificial element made by man?
A.Gallium
B.Iron
C.Helium
D.Americium

Answer 1

Hint: Basically, a synthetic element also known as artificial or man-made elements is one of 24 chemical elements that do not occur naturally on Earth. That element is created by human manipulation of fundamental particles in a nuclear reactor or by the explosion of the atomic bomb.

Complete step by step answer:
Some of the chemicals do not occur naturally on Earth and hence these chemically are created by man. So far, only 24 elements are considered as artificial or man made elements. These are those with atomic number 95-118. These elements were created between 1994 and 2010. Moreover, all the synthetic elements are unstable but they decay at a widely varying rate. Their half-lives generally range from 15.6million years to a few hundred microseconds. So, form the given options Americium is an artificial element with atomic number 95.
It is a human-made actinide element and has no stable isotopes. It was discovered by Glenn Seaborg, Leon Morgan, Ralph James and Albert Choirs in 1944. The americium metal generally reacts with oxygen and dissolves in aqueous acids. The most stable oxidation state of this element is +3. Americium compounds with oxidation state +4 and higher are strong oxidizing agents.

Hence, option D is correct.

Note: Americium is used in very small quantities in household ionization smoke detectors. It plays a part in nuclear power production as a decay product. Due to scarcity of Plutonium to make spacecraft batteries, americium can serve as a viable replacement in the forthcoming years.