Question

First: Identify the element from clue 16 ---- Period 6, Group 1. hint number 55 (Name and Atomic number, please 2 points) Second: you must "cross a divide". When you land back on "solid ground" there is a silvery white metal with an average mass of 178.5 amu. From there --- add 7 protons! Identify the element and describe the final steps you used to solve this last clue! (4 points)

Answer 1

Let's tackle the clues step by step.

First Clue: Identify the Element from Clue 16

• Period 6, Group 1 corresponds to Francium (Fr), which has an atomic number of 87.

So for the first part, the answer is:

• Element: Francium
• Atomic Number: 87

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Second Clue: "Cross a Divide" and Identify the Element

• The phrase "cross a divide" suggests moving from one side of the periodic table to another or possibly moving between groups or periods.
• "Silvery white metal with an average mass of 178.5 amu": The element that fits this description is Tantalum (Ta), which is found in Group 5, Period 6, and has an atomic mass near 178.5 amu.

Now, according to the clue, we need to "add 7 protons":

• Tantalum (Ta) has an atomic number of 73.
• Adding 7 protons to Tantalum's atomic number gives us:
  \( 73 + 7 = 80 \).

The element with atomic number 80 is Selenium (Se).

Final Steps:

1. Identified the silvery white metal with an average mass of 178.5 amu to be Tantalum (Ta).
2. Noted its atomic number of 73.
3. Added 7 protons to get the new atomic number: \( 73 + 7 = 80 \).
4. The element with atomic number 80 is Selenium (Se).

So for the second part, the answer is:

• Element: Selenium
• Atomic Number: 80