<span>Valence is defined as number of electrons that are present in the outermost orbital. Oxygen is in the 16th column of the periodic table and the total number of valance electrons is determined by units place digit of the column position which is 6 for oxygen. The outermost orbital is the high energy level and there are two in that orbit. So the valance is +2.</span>
<u>Answer</u>: D. calcium chloride
<em>Calcium chloride molecules can be ruled out as the mystery molecule</em>
<u>Explanation:</u>
<em>Artificial membranes are also called as the synthetic membranes.</em> It is created synthetically for the <em>special separation purpose in the laboratory. </em>
It is used to separate large molecules like <em>solid particles and big biological molecules like protein, DNA. </em>
They are produced from organic materials. <em>Calcium chloride contains the chloride ion and calcium ion,</em> as the chloride ion easily passes the artificial membrane so we can term <em>calcium chloride as the mystery membrane that passes the artificial membrane easily.</em>
The function of protein that helps chemical react is catalyzing