Calcula la cantidad de gramos que hay en 12,5 mol de NaCl (Masa Na: 23,0; Cl: 35,5).

731.25 g

Explanation:

The question asks us to calculate the mass of 12.5 moles of NaCl. The individual relative atomic masses of the elements were supplied. We must first obtain the molar mass of sodium chloride as follows;

Molar mass of sodium chloride= 23.0 + 35.5 = 58.5 gmol-1

From the formula;

Number of moles (n) = mass /molar mass

Number of moles of sodium chloride= 12.5 moles

Mass of sodium = The unknown

Molar mass of sodium chloride= 58.5gmol-1

Mass of sodium chloride= number of moles × molar mass

Mass of sodium chloride= 12.5 × 58.5

Mass of sodium chloride= 731.25 g

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.

16

explanation:

the marks go by 4s