Answer:
Explanation: In the previous section we listed four characteristics of radioactivity and nuclear decay that form the basis for the use of radioisotopes in the health and biological sciences. A fifth characteristic of nuclear reactions is that they release enormous amounts of energy. The first nuclear reactor to achieve controlled nuclear disintegration was built in the early 1940s by Enrico Fermi and his colleagues at the University of Chicago. Since that time, a great deal of effort and expense has gone into developing nuclear reactors as a source of energy. The nuclear reactions presently used or studied by the nuclear power industry fall into two categories: fission reactions and fusion reactions
Answer:
The answer to your question is: letter A.
Explanation:
A Covalent bond polar is between 2 non metals where one atom is bigger than the other one so the distribution of charges creates this polarity.
A. One atom attracts shared electrons more strongly than the other atom This is the correct definition of bond polar, one element is bigger and stronger than the other element.
B. One atom has transferred its electrons completely to another atom This definition is incorrect, it is the definition of ionic bonding.
C. A sea of electrons has been created between the elements This definition is incorrect for the polar bond, it describes a metallic bonding.
D. Two atoms are sharing electrons with equal attraction This definition is incorrect for a polar bond, but is the correct definition for nonpolar bonding.
The answer is C. They lower the activation energy of an elementary step of a reaction
This makes the reaction rate to increase since less energy is required to make a reaction occur.
