MW of gas : 124.12 g/mol
<h3>Further explanation </h3>
Density is a quantity derived from the mass and volume
Density is the ratio of mass per unit volume
With the same mass, the volume of objects that have a high density will be smaller than objects with a smaller type of density
The unit of density can be expressed in g/cm³ or kg/m³
Density formula:

ρ = density
m = mass
v = volume
glass vessel wieight = 50 g
glass vessel + liquid = 148 ⇒ liquid = 148 - 50 =98 g
volume of glass vessel :

An ideal gas :
m = 50.5 - 50 = 0.5 g
P = 760 mmHg = 1 atm
T = 300 K

For example, the atomic mass of an oxygen atom is 16.00 amu; that means the molar mass of an oxygen atom is 16.00 g/mol. Further, if you have 16.00 grams of oxygen atoms, you know from the definition of a mole that your sample contains 6.022 x 10^23 oxygen atoms.
Density = m/v therefore v = m/d v = 25/0.85 v = 29.4117... cm^3 ( = 2.94 * 10^-5 m^3
Answer:
the newspaper one is a chemical change because the chemicals in the paper have reacted with something and turned a different color. the wax one is a physical change because it is a change in the phase of matter, which is always a physical change (still the same substance chemically)