In what respect does an atom of magnesium differ from a magnesium ion (mg^{2+})?
a. the ion has a more stable electronic arrangement than the atom.
b. the positive charge on the nucleus of the ion is two units greater than the nuclear charge on the atom.
c. the ion has two more protons than the atom.
d. the ion will react more readily with free cl₂. (e)the ion has two more planetary electrons than the atom. can anyone explain this one?

the best answer is d because the strong cohesion is caused by the ability of water molecules to undergo hydrogen bonding.

a is incorrect because when water solidifies, it becomes   ice, which expands and occupies a bigger volume for the same mass of water in its liquid state.

b is incorrect because water has high surface tension. besides bonding to itself it hydrogen bonds to other molecules at the top decreasing possibility for breaking of attractive forces.

c is incorrect because the water molecule has oxygen which is highly electronegative and so pulls the electron pair towards itself creating a dipole moment, making the molecule polar.

e is incorrect because water has strong adhesion, ability to stick to other molecules such as glass because of this molecules having stronger hydrogen bonding than water.

a saline water is fed to a reverse osmosis unit at flow rate o rotameter connected to reject (retentate) line reads 8 installed in reject and permeate line reads 15.2 milli siemens/cm and 300 micro siemens/com respectively.