What is the principal quantum number for the outermost electron in sodium (Na)?
Practice Questions
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What is the principal quantum number for the outermost electron in sodium (Na)? (2022) 2022
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Questions & Step-by-Step Solutions
What is the principal quantum number for the outermost electron in sodium (Na)? (2022) 2022
Step 1: Find the atomic number of sodium (Na). Sodium has an atomic number of 11.
Step 2: Understand that the atomic number tells us the number of electrons in a neutral atom. So, sodium has 11 electrons.
Step 3: Determine how the electrons are arranged in shells. The first shell can hold 2 electrons, the second shell can hold 8 electrons, and the third shell can hold more.
Step 4: Fill the first shell with 2 electrons. Now we have 11 - 2 = 9 electrons left.
Step 5: Fill the second shell with 8 electrons. Now we have 9 - 8 = 1 electron left.
Step 6: The remaining 1 electron goes into the third shell. This means the outermost electron is in the 3rd shell.
Step 7: The principal quantum number (n) corresponds to the shell number where the outermost electron is located. Since the outermost electron is in the 3rd shell, n = 3.
