an element's name, chemical symbol, atomic number, atomic mass.
IDK what you are even asking for
The molecular formula will be a multiple of the empirical CH2O. One unit of CH2O has a mass of 12+2*1+16 = 30 g. This means that if our compound has a molecular mass of 180 g/mol, we can divide 180 / 30 = 6 units, and our compound has 6 units of CH2O. This means that its molecular formula is C6H12O6.
The atomic mass is determined by the number of protons and neutrons in a atoms for example oxygen has eight protons and neutrons which gives oxygen and atomic mass of 16
Pushing down a piston in an airtight cylinder would tend to increase the pressure in the system since the particle collision and collisions with the walls are now more frequent. Also, pushing further, the gas would undergo a phase change from gas to a liquid.