A. hex- Normally with 6, the prefix is hex-. For example a polygon having 6 sides is known as hexagon.
Kr 5s2 is the correct noble gas configuration for strontium
Mercury-199 is composed of 80 protons, 119 neutrons, and 80 electrons.
Thermodynamically favored process are those processes that do not require any assistance from outside the system e.g water boils at 25 degrees. Thermodynamically unfavored processes require assistance from outside to induce the required change for example water doesn't freeze at 15 degrees and therefore for that to happen several factors in the system have to be modified to achieve this. Therefore, there is a possibility of companies to produce product by using thermodynamically unfavored process by inducing changes in the system to achieve desired change or modification.