Question

1. identify the atom using the model:______

(draw it if you need too.)
electron shells:

• shell 1:
• shell 2:
• shell 3:

1. nitrogen has 7 protons. which model below represents an ion, and which represents an isotope?

statements to help guide you:

• in all nitrogen atoms, the number of ______ stays the same.
• in an isotope, the number of ______ changes, but the number of protons stays the same.
• in an ion, the number of ______ changes, which causes the atom to have a charge.

which model is the ion? ______
which model is the isotope?______

Explanation:

For Question 3:

Step1: Calculate total electrons

$2 + 8 + 3 = 13$

Step2: Match electrons to proton count

Neutral atom: protons = electrons = 13

1. All nitrogen atoms have a fixed number of protons (7, given). Isotopes of an element have the same number of protons but different numbers of neutrons. Ions form when an atom gains/loses electrons, so electron count differs from proton count, creating a charge.
2. Model 1 has 7 protons, 7 neutrons, and 7 electrons (matches neutral nitrogen). Model 2 has 7 protons, 7 neutrons, but only 2 electrons (electron count ≠ proton count, so it is an ion). Model 3 has 7 protons but 6 neutrons (neutron count differs from the standard 7, so it is an isotope).

Answer:

Aluminum (Al)

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For Question 4: