<span>The mass of an object is measured in either grams or kilograms. Mass is best described as the amount of matter, or "stuff," in a solid, and is different from weight (which is the force of gravity on an object). Since mass is used with solids, it will be measured in grams or kilograms (rather than in something like liters, which would be used with the volume of a liquid). To measure mass, you can use a balance, for example a triple balance beam.</span>
Answer: The density of the object will be 
Explanation:
Density is defined as the mass contained per unit volume.

Given : Mass of object = 19.6 grams
Volume of object= 
Putting in the values we get:

Thus density of the object will be 
the element chlorine is represented by the symbol Cl
The molecular weight of a given compound would simply the
sum of the molar weights of each component.
The molar masses of the elements are:
C = 12 amu
H = 1 amu
N = 14 amu
O = 16 amu
where 1 amu = 1 g / mol
Since there are 6 C, 5 H, 1 N and 2 O, therefore the
total molecular weight is:
molecular weight = 6 (12 amu) + 5 (1 amu) + 1 (14 amu) +
2 (16 amu)
molecular weight = 123 amu
Therefore the molecular weight of nitrobenzene is 123 amu
or which is exactly equivalent to 123 g / mol.
1.07 mol would be your answer