A Cobalt (Co) atom has a mass number of 60. Its atomic number is 27. How many neutrons does the cobalt atom have?
The Correct Answer and Explanation is:
To determine the number of neutrons in a cobalt (Co) atom, we use the following formula:
Number of neutrons = Mass number – Atomic number
For cobalt:
- Mass number = 60
- Atomic number = 27
Now subtract the atomic number from the mass number:
60 – 27 = 33
Answer: The cobalt atom has 33 neutrons.
Explanation
Atoms are made up of three subatomic particles: protons, neutrons, and electrons. Protons and neutrons are located in the nucleus of the atom, while electrons orbit around the nucleus. The atomic number of an element tells us the number of protons in the nucleus. Since atoms are electrically neutral, the number of electrons is equal to the number of protons.
Cobalt has an atomic number of 27, which means every cobalt atom contains 27 protons. The mass number is the total count of protons and neutrons in the nucleus. In this case, the mass number is given as 60. Neutrons have no electric charge, but they do contribute to the mass of the atom.
To find the number of neutrons, we subtract the number of protons from the mass number:
Mass number (60) – Atomic number (27) = 33 neutrons
So a cobalt atom with a mass number of 60 has 33 neutrons in its nucleus.
It is important to note that the mass number given here refers to a specific isotope of cobalt. Isotopes are atoms of the same element that have the same number of protons but different numbers of neutrons. The most common isotope of cobalt is cobalt-59, which has 32 neutrons. However, this particular cobalt atom has a mass number of 60, indicating it is a different isotope with 33 neutrons.
Understanding how to calculate neutrons helps in identifying isotopes and understanding nuclear stability. Neutrons play a key role in keeping the nucleus stable by offsetting the repulsive forces between the positively charged protons.
