Answer: Antoine Lavoisier.
He classified the elements into four groups: elastic fluids, nonmetals, metals and earths. Some of the called elementes were not really elements (light and heat). Others were compounds, e.g. hydrochloric acid.
I understand here "bias" to be the uncertainty of measurements. So the order will be the following:
6.4 ± 0.5 s
<span>6.6 ± 0.1 s,
</span><span>6.63 ± 0.01 s,
</span><span>6.52 ± 0.05 s,
</span>
(notice how the second number, the one behind the symbol ± gets smaller, as the bias gets smaller).
The answer is <span>a. Rubidium
A cation is an ion that has a positive charge. The charge positive because it loses electrons. The radius of an atom is influenced by the electron because it is found at the outer layer of the atom. Since cation has less electron and anion get more electron, the radius of cation will be smaller than anion.
Rubidium is the biggest cation because it is located in the lowest row, thus having most electron count.</span>
Look kid, this question has been up for 17 hours think its time to let it go......... hoped i helped. ✔verified✔