The correct one is Respiratory Distress !!
As rest are not concerned with air pollution !!
Atomic radius defines the size of an atom.
Explanation:
Atomic radius is defined as “one-half the distance between the nuclei of two identical atoms that are bonded together.” If ‘r’ is the atomic radius and ‘d’ the distance in between nuclei of two atoms that are identical and bonded, then r = d/2.
The units used to express atomic radius are picometer, nanometer, and Angstroms.
In the periodic table, the atomic radius of elements decreases with elements across a <em>period</em> (left-right) and increases with elements down a group.
Go here and see how:
http://www.rsc.org/learn-chemistry/resource/res00000698/using-indigestion-tablets-to-neutralise-an-acid?cmpid=CMP00005978
The salt that its aqueous solubility most sensitive to pH would be calcium fluoride (CaF2). It is an insoluble salt which when reacted with an acid, it yields this equation:
<span>CaF2 (s) + 2 HX (aq) → 2 HF (aq) + CaX2 (aq)
</span>
Since it produces H+ and and OH- when combined with water, it is therefore sensitive to pH.
