Problem 50 - Chemistry An Atoms First Approach

Question

What is the symbol of an ion with 16 protons, 18 neutrons, and 18 electrons? What is the symbol for an ion that has 16 protons, 16 neutrons, and 18 electrons?

Step-by-Step Solution

Answer

The symbols for the ions are: \( {^{34}_{16} S^{2+}} \) and \( {^{32}_{16} S^{2+}} \).

Step 1: Determine the atomic number for both ions

The atomic number is the number of protons in the nucleus of an atom. Since both ions have 16 protons, the atomic number for both ions is 16.

Step 2: Identify the element

The atomic number corresponds to a specific element on the periodic table. An atomic number of 16 corresponds to the element sulfur (S).

Step 3: Determine the mass number for each ion

The mass number of an atom is the sum of the number of protons and neutrons in the nucleus. For the first ion, 16 protons + 18 neutrons = 34. For the second ion, 16 protons + 16 neutrons = 32.

Step 4: Determine the charge for each ion

To find the charge of each ion, we need to compare the number of electrons to the number of protons: 1) Ion 1: 18 electrons, 16 protons => Charge = 18 - 16 = +2 2) Ion 2: 18 electrons, 16 protons => Charge = 18 - 16 = +2

Step 5: Write the atomic symbol for each ion

To write the atomic symbol, we use the format: \( {^{Mass\ Number}_{Atomic\ Number} Element Symbol^{Charge}} \) 1) For the first ion with a mass number of 34, atomic number of 16, and a charge of +2, it will be: \( {^{34}_{16} S^{2+}} \) 2) For the second ion with a mass number of 32, atomic number of 16, and a charge of +2, it will be: \( {^{32}_{16} S^{2+}} \) So the symbols for the given ions are: \( {^{34}_{16} S^{2+}} \) and \( {^{32}_{16} S^{2+}} \).