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 get by with a single test, you get 100 super-geek points from your research lab team. Pick your two tests, number them as #1 and #2, and justify why you think these two will certainly be enough (and why the first might well be enough all by itself.) The available tests are classification into metal, non-metal, 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), and boiling point (error range: +/- 20 C).

Answer 1

#1 atomic radius.

Step-by-step explanation:

Hello,

In this case, since time and money are critical and additional points are given if one test is used, the best one would be the determination of the atomic radius including the error range of +/-1 pm. This lies on the fact that the atomic radius varies group-by-group by no less than 5 pm per element. For instance, nitrogen's atomic radius is about 56 pm and oxygen's one 48 pm (difference is more than 5pm), therefore, even with the associated error, such technique will be accurate in the light of the identification of the mysterious element with just one test.

Best regards.

Answer 2

Due to time and money constraint, the two possible tests that you could conduct are (#1)electronegativity test and (2)melting point. Other tests like the classification of metal/non-metal/metalloid, count of valence electron shells, and atomic radius can yield results that may refer to a lot of elements. On the other hand, electronegativity is specific and unique to every element. And also, it has the lowest error range (+/- 1 pm). Same applies with the boiling point which is also unique to every element.