Determine the number of protons and the number of electrons in each ion. a. Ni²⁺ b. S^2– c. Br^– d. Cr³⁺

Verified step by step guidance

1. Identify the atomic number of Nickel (Ni) from the periodic table. The atomic number represents the number of protons in a neutral atom.
2. For the Ni2+ ion, the number of protons remains the same as in the neutral atom because the atomic number does not change.
3. Understand that the charge on an ion indicates the loss or gain of electrons. A positive charge (Ni2+) means that electrons are lost.
4. Calculate the number of electrons in Ni2+ by subtracting the charge from the number of electrons in a neutral Nickel atom. In a neutral atom, the number of electrons equals the number of protons.
5. Summarize the findings: The number of protons in Ni2+ is equal to the atomic number of Nickel, and the number of electrons is the atomic number minus 2.

Key Concepts

Atomic Structure

Atoms consist of protons, neutrons, and electrons. Protons are positively charged particles found in the nucleus, while electrons are negatively charged and orbit the nucleus. The number of protons defines the element, and in a neutral atom, the number of electrons equals the number of protons.

Ions

Ions are atoms or molecules that have gained or lost one or more electrons, resulting in a net charge. Cations are positively charged ions formed by losing electrons, while anions are negatively charged ions formed by gaining electrons. The charge of an ion indicates the difference between the number of protons and electrons.

Nickel Ion (Ni2+)

Nickel (Ni) has an atomic number of 28, meaning it has 28 protons in its neutral state. The Ni2+ ion indicates that the nickel atom has lost two electrons, resulting in a positive charge. Therefore, in the Ni2+ ion, there are 28 protons and 26 electrons.