Cobalt (Co) has an atomic mass of 59 and an atomic number of 27. Which statement correctly describes an atom of cobalt?
What is it?
To determine the correct statement that describes an atom of cobalt (Co), we need to understand the meaning of atomic mass and atomic number.
Atomic number (Z) represents the number of protons in the nucleus of an atom. In the case of cobalt, the atomic number is 27. This means that an atom of cobalt has 27 protons.
Atomic mass (A) represents the average mass of an atom, taking into account the total number of protons and neutrons in the nucleus. In the case of cobalt, the atomic mass is given as 59.
Based on this information, we can determine the correct statement:
Statement 1: An atom of cobalt (Co) has 59 neutrons.
To find the number of neutrons, we subtract the atomic number from the atomic mass: A - Z = number of neutrons. Therefore, in this case, 59 - 27 = 32. So, an atom of cobalt actually has 32 neutrons.
Hence, Statement 1 is incorrect.
Statement 2: An atom of cobalt (Co) has 27 electrons.
The number of electrons in an atom is equal to the number of protons. Since the atomic number of cobalt is 27, this means that an atom of cobalt has 27 electrons.
Therefore, Statement 2 is correct.