Lithium has 3 protons. How many neutrons are in the isotope lithium-8?

Step 1: Define the Problem

Identify the number of neutrons in the isotope lithium-8, given that lithium has 3 protons.

Step 2: Break Down the Problem

1. Determine the atomic number of lithium.
2. Understand the concept of isotopes.
3. Calculate the number of neutrons.

Step 3: Apply Relevant Concepts

• Atomic Number: The atomic number of lithium is 3, which means it has 3 protons.
• Isotopes: Isotopes of an element have the same number of protons but different numbers of neutrons.
• Mass Number: The mass number of an isotope is the sum of protons and neutrons.

Step 4: Analysis, Verify and Summarize

• Mass Number of Lithium-8: 8
• Number of Protons in Lithium: 3
• Number of Neutrons: Mass number - Number of protons = 8 - 3 = 5

Final Answer

Lithium-8 has 5 neutrons.