Iodine is one of seven elements that usually form as diatomic molecules. These other "diatomics" are

and

. They typically bond to themselves.
Iodine has seven valence electrons. Using valence shell electron pair repulsion (VSEPR) theory, we can predict the Lewis dot structure for

. We see there are fourteen electrons, and we can make a covalent bond, leaving three lone pairs on each atom. The bond replaces two electrons, so the number of electrons shared is two.
I think the correct answer from the choices listed above is option C. There would be 150 sodium ions that will be transported across the cell membrane. Each ATP molecule aids in moving 3 Na+ across the membrane. So, 50 times 3 is equal to 150.
<span>100,000 times more. The rule is that the product of the concentration of (H+) and (OH-) in molars is always 10^-14 (if it is more, they combine and produce simple water which brings the product back down to this number again. If it is less, water molecules will split to bring the product back up to equilibrium).
pH 9 means (H+) is 10^-9 molar. But that means (OH-) is 10^-5 at the same time.
pH 4 means (H+) is 10^-4 molar. But that means (OH-) is 10^-10 at the same time.
10^-5 / 10^-10 = 10^5 or 100,000 times more.</span>
Answer: 1Ca + 2O + 2H
Explanation:
Ca is 1 since there is no subscript
O and H each have 2 because the subscript 2 is outside the parenthesis so you multiply their subscript (1) by 2