Question

Calculate the theoretical density of mgo, given that it has the rock salt crystal structure. the ionic radii of mg²⁺ and o²⁻ in mgo are 72 pm and 140 pm, respectively. what is the density of mgo in g/cm³? consider the unit cell is cubic.

Answer 1

To calculate the theoretical density of MgO with a rock salt crystal structure, use the given X-ray density and observed density in the formula to find the molar volume.

Step-by-step explanation:

Theoretical density can be calculated by dividing the molar mass of the substance by the molar volume of the unit cell. In the case of MgO with a rock salt crystal structure, the molar volume can be determined using the formula:

Molar volume = Molar mass / Density

The density of MgO can be found using the given information:

X-ray density = 6.806 g/cm³ and observed density = 6.67 g/cm³

By substituting the values into the formula, we can find the molar volume:

Molar volume = (58.69 + 16.00) / 6.806 cm³/mol = 10.97 cm³/mol