Question

Imagine you are given a mystery element. It is, however, a discovered and known element. You may perform a maximum of two observations or tests to determine its identity. Time and money is critical, so you need to prioritize your tests. If you can identify the mystery element with a single test, you get 100 super-geek points from your research lab team.

Pick two tests and justify why you think they will identify the mystery element with certainty. If you think the first test will be enough, explain why.

Choose from these available tests:
• classification into metal, nonmetal, or metalloid
• count of valence electrons
• count of electron shells
• atomic radius (error range: +/- 1 pm)
• electronegativity (error range: +/- 0.1)
• first ionization energy (error range: +/- 10 kJ/mole)
• melting point (error range: +/- 10 C)
• boiling point (error range: +/- 20 C)

Answer 1

Count of Valence electron followed by electron shells

Step-by-step explanation:

The periodic table has certain very unique properties that help identify the elements.

The number of valence electrons in any element can be determined by the placement of the element in the group. An element from group III will have three valence electrons.

Hence, this test will help locate the group of the element in question.

This test should be followed by the number of electron shells.

In the Periodic table, the placement of any element in the row depends on the number of electron shells. An element from row II will have two electron shell.

These two tests will work like coordinates on the Periodic Table.

For example, the result is Group II, Row 3 is Calcium.

Answer 2

The classification of it being a metal, nonmetal, or metalliod will be useful in the process of elimination to determine what it is. Then for the second test, meauring the atomin radius will narrow it down quicker to the mystery elemet's name.

Since you determined what part of the periodic table it's on, then when measuring the atomic radius, you should be able to pinpoint what the element is more surely.