The element argon has three naturally occurring isotopes, with \(18,20,\) and 22 neutrons in the nucleus, respectively. (a) Write the full chemical symbols for these three isotopes. (b) Describe the similarities and differences between the three kinds of atoms of argon.

To write the chemical symbols for the isotopes of argon, we need to find the atomic number of argon, denoted by 'Z', which represents the number of protons in the nucleus. You can find this information on the periodic table. In the case of argon, the atomic number is 18.

The chemical symbol for argon is 'Ar'. For isotopes, we write their mass number (the total of protons and neutrons) on the top left corner and the atomic number on the bottom left corner of the chemical symbol. The mass number (A) is the sum of protons (Z) and neutrons (N). Since argon has 18 protons, we can calculate the mass number for each isotope using their neutron numbers. Isotope 1 (18 neutrons): \(A = Z + N = 18 + 18 = 36\), which gives us the chemical symbol: \(_{18}^{36}\textrm{Ar}\) Isotope 2 (20 neutrons): \(A = Z + N = 18 + 20 = 38\), which gives us the chemical symbol: \(_{18}^{38}\textrm{Ar}\) Isotope 3 (22 neutrons): \(A = Z + N = 18 + 22 = 40\), which gives us the chemical symbol: \(_{18}^{40}\textrm{Ar}\)

Now let's discuss the similarities and differences between these three isotopes of argon: Similarities: 1. All three isotopes have the same atomic number (18 protons), which means they are all argon atoms. 2. The number of electrons in all three isotopes is the same (18 electrons), resulting in the same chemical behavior and properties. Differences: 1. The isotopes have different numbers of neutrons: 18, 20, and 22 neutrons, respectively. 2. They have distinct mass numbers: 36, 38, and 40, respectively. Consequently, the isotopes have slightly different physical properties, such as densities or atomic masses. In summary, the full chemical symbols for the three naturally occurring isotopes of argon are \(_{18}^{36}\textrm{Ar}\), \(_{18}^{38}\textrm{Ar}\), and \(_{18}^{40}\textrm{Ar}\). Their similarities include the same atomic number and chemical behavior, while their differences lie in their neutron numbers and mass numbers, resulting in distinctive physical properties.