Problem 5 - Chemistry An Atoms First Approach

Question

Which of the following explain how an ion is formed? Explain your answer. a. adding or subtracting protons to/from an atom b. adding or subtracting neutrons to/from an atom c. adding or subtracting electrons to/from an atom

Step-by-Step Solution

Answer

An ion is formed by adding or subtracting electrons to/from an atom, as described in option c. Gaining or losing electrons gives the atom a net charge, creating an ion. Changing the number of protons (option a) or neutrons (option b) does not result in ion formation. Instead, it creates new elements or isotopes, respectively.

Step 1: Understand Ion Formation

An ion is an atom that has an unequal number of protons and electrons, which gives it a net electrical charge. In order to form an ion, an atom has to either gain or lose electrons. This process does not involve adding or removing protons or neutrons.

Step 2: Analyze Option a

Option a suggests that ions are formed by adding or subtracting protons to/from an atom. However, adding or subtracting protons would change the atomic number of the element, creating a different element altogether, not an ion. Hence, this option is incorrect.

Step 3: Analyze Option b

Option b suggests that ions are formed by adding or subtracting neutrons to/from an atom. The number of neutrons in an atom affects its mass and stability but not its charge. Changing the number of neutrons results in isotopes of the same element but does not create ions. So, this option is also incorrect.

Step 4: Analyze Option c

Option c suggests that ions are formed by adding or subtracting electrons to/from an atom. When an atom gains or loses electrons, it acquires a net charge, making it an ion. If an atom loses one or more electrons, it becomes positively charged and is called a cation. If an atom gains one or more electrons, it becomes negatively charged and is called an anion.

Step 5: Conclusion

Option c correctly describes how ions are formed by adding or subtracting electrons to/from an atom. This process gives the atom a net charge, creating an ion. Thus, the correct explanation for ion formation is option c.