Question

directions: use a periodic table to determine the atomic mass, atomic number, number of protons, electrons, and neutrons for each element. next, complete the bohr model.
lithium ion
atomic number: 3
atomic mass
number of protons
number of electrons
number of neutrons
oxide ion
atomic number
atomic mass
number of protons
number of electrons
number of neutrons
calcium ion
atomic number
atomic mass
number of protons
number of electrons
number of neutrons

Explanation:

Step1: Lithium Ion

• Atomic Mass: From periodic table, atomic mass of Li is approximately \(6.94\approx7\).
• Number of Protons: Atomic number \(Z = 3\), so number of protons \(p=3\).
• Number of Electrons: \(Li^{+}\) has lost 1 electron. So number of electrons \(e=3 - 1=2\).
• Number of Neutrons: \(n=\text{Atomic Mass}-\text{Atomic Number}=7 - 3 = 4\).

Step2: Oxide Ion

• Atomic Number: From periodic table, for oxygen \(Z = 8\).
• Atomic Mass: Approximately \(16\).
• Number of Protons: \(p = 8\).
• Number of Electrons: \(O^{2-}\) has gained 2 electrons. So \(e=8 + 2=10\).
• Number of Neutrons: \(n=16 - 8=8\).

Step3: Calcium Ion

• Atomic Number: From periodic table, for calcium \(Z = 20\).
• Atomic Mass: Approximately \(40\).
• Number of Protons: \(p = 20\).
• Number of Electrons: \(Ca^{2+}\) has lost 2 electrons. So \(e=20 - 2=18\).
• Number of Neutrons: \(n=40 - 20=20\).

Answer:

Ion	Atomic Number	Atomic Mass	Number of Protons	Number of Electrons	Number of Neutrons
\(O^{2-}\)	\(8\)	\(16\)	\(8\)	\(10\)	\(8\)
\(Ca^{2+}\)	\(20\)	\(40\)	\(20\)	\(18\)	\(20\)