An amino acid is usually more soluble in aqueous solvent at pH extremes than it is at a pH near the isolelectric point of the am
ino acid. (Note that this does not mean that the amino acid is insoluble at a pH near its pI.) Which of the following statements correctly explains this phenomenon?
(Select all that apply.)
A. The neutral charge of an amino acid molecule at its isoelectric point will make the molecule hydrophobic.
B. At pH extremes, the amino acid molecules mostly carry a net charge, thus increasing their solubility in polar solvent.
C. At very low or very high pH, the amino acid molecules have increased charge, thus form more salt bonds with water solvent molecules.
D. At pH values far from the isoelectric point, individual amino acid molecules have greater kinetic energy, thus more readily stay in solution.
Group 2A — The Alkaline Earth Metals. Group 2A (or IIA) of the periodic table are the alkaline earth metals: beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), and radium (Ra).
<em><u>Oxidation is defined as the loss of electrons by an atom while reduction is the gain of electrons by an atom</u></em>.
Atoms of elements have an oxidation number of Zero in their elemental state.
When an atom looses electrons it undergoes oxidation and its oxidation number increases.
For example, <em><u>an atom of sodium (Na) at its elemental state has an oxidation number of 0. When the sodium atom looses an electrons it becomes a cation, Na+, with an oxidation number of +1 , the loss of electron shows an increase in oxidation number from 0 to +1.</u></em>