An element is a chemical substance made up of a particular kind of atom and hence cannot be broken down or transformed by a chemical reaction into a different element, though it can be transmuted into another element through a nuclear reaction.
Almost 40 years separate Shirley Ann Jackson's achievement, as the first African-American woman to earn a Ph.D. in theoretical high energy physics at Massachusetts Institute of Technology, and Jedidah Isler, the first African-American woman to receive a Ph.D. in Astrophysics from Yale.
Shirley Chisholm was the first black woman elected to Congress in 1968. On January 25, 1972, she became the first major-party black candidate for President of the United States and the first woman to run for the Democratic presidential nomination.