Report your answer with the proper number of significant figures. Magnesium is used in lightweight alloys for airplane bodies and other structures. The metal is obtained from seawater in a process that includes precipitation, neutralization, evaporation, and electrolysis. How many kilograms of magnesium can be obtained from 4.29 km3 of seawater if the initial Mg2 concentration is 0.19% by mass

8.47 * 10^9 Kg

Explanation:

Density of sea water = 1040 kg/m^3

mass of sea water = ?

Volume of sea water = 4.29 * 10^3 m^3

Mass of sea water = 1040 kg/m^3 * 4.29 * 10^9 m^3

Mass of sea water = 4.46 * 10^12 Kg

Mass of Mg2+ =  0.19% by mass

So;

Mass of Mg2+ =0.19/100 * 4.46 * 10^12 Kg

Mass of Mg2+ = 8.47 * 10^9 Kg

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.

they vary. it used to be meat, grain, bread, candy, beverages, donuts, and fruits/vegetables. now they added exercise in.