Explain how you would decide which represents a greater mass: 3.25 x 1022 atoms of Ca or 2.45 grams of Mg?

Mg

Explanation:

Given data:

Number of atoms of Ca = 3.25×10²²

Mass of Mg = 2.45 g

which has greater mass = ?

Solution:

1 mole = 6.022 ×10²³ atoms

3.25×10²² atoms × 1 mol/6.022 ×10²³ atoms

0.54×10⁻¹ mol

0.054 mol

Mass of Ca:

Mass = number of moles × molar mass

Mass = 0.054 mol × 40 g/mol

Mass = 2.16 g

Mass of Mg = 2.45 g

The  3.25×10²² atoms of Ca has 2.16 g mass while the other given Mg has 2.45 g mass. Thus Mg has greater mass.

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.

2b2t

explanation:

2b2t