A crystal mth a simple cubic lattice and a monoatomic basis has an atomic ra- dius of 2.5 A and an atomic weight of 5.42. Calculate its density, assuming that the atoms touch each other.

density = 0.071984 g/cm³

Explanation:

For a simple cubic lattice structure;

There are 8 atoms in the unit cell, with each edge of the cell contributing 1/8th atom to one unit cell.

Thus, in a unit cell, the required number of atoms = 8/8 = 1

The mass of the unit cell can be calculated by using the formula:

Similarly, given the atomic radius = 2.5 angstrom =

Thus, volume V = a³

The edge length for the simple cubic radius  is:

a = 2 × r

a = 2 ×

a = m

a =

Now;

volume V = a³

volume V =

volume V = cm³

Finally; the density = mass/volume

density =  

density = 0.071984 g/cm³

a). in this case, dh> 0 and sd> 0. if t becomes larger, the term "-tds" will become more negative. at some point, it is possible that -dts will be more negative than the dh is positive, and the reaction will become spontaneous. this is probably the correct answer, but you should look at all of the other possibilities and make sure of that.