Answer :
Final answer:
The question pertains to the element bismuth, which is a chemical element with 83 protons, 127 neutrons, and 83 electrons, denoted as Bi. Bismuth is known for its unique crystalline structure and was once considered stable but has an extremely long radioactive half-life. The properties of other elements and their isotopes, such as sodium, xenon, arsenic, and radium, are also provided for comparison.
Explanation:
The question relates to the properties of a bismuth atom, which is a chemical element with the atomic number 83. Bismuth is characterized by having 83 protons, 127 neutrons, and 83 electrons when it is neutral. It is symbolized by 'Bi' and is known for its crystalline structure, which can be synthetically prepared to form bismuth crystals. While traditionally thought to be stable, the isotope of bismuth with the mass number 209 has been found to be weakly radioactive with an exceptionally long half-life, highlighting the complexity and wonder of atomic structures and their isotopes.
Referencing the provided numbered points:
- (a) Sodium (Na), with 11 protons and a mass number of 23, is an alkali metal.
- (b) Xenon (Xe), which has 54 protons (and thus 54 electrons in the neutral atom) and 75 neutrons, is a noble gas.
- (c) An isotope with 33 protons and 40 neutrons in its nucleus refers to arsenic-73 (Arsenic).
- (d) Radium (Ra), with 88 electrons and 138 neutrons, is an alkaline earth metal.
Additional examples provided include 212Pb decaying into 212Bi (bismuth), emphasizing the transmutation processes that can occur naturally among isotopes through radioactive decay.
