"A <span>gas condensing to a liquid" is the one system among the following choices given in the question where the entropy is decreasing. The correct option among all the options that are given in the question is the fourth option or option "D". I hope that this is the answer that has come to your desired help.</span>
Enthalpy of formation is calculated by subtracting the total enthalpy of formation of the reactants from those of the products. This is called the HESS' LAW.
ΔHrxn = ΔH(products) - ΔH(reactants)
Since the enthalpies are not listed in this item, from reliable sources, the obtained enthalpies of formation are written below.
ΔH(C2H5OH) = -276 kJ/mol
ΔH(O2) = 0 (because O2 is a pure substance)
ΔH(CO2) = -393.5 kJ/mol
ΔH(H2O) = -285.5 kJ/mol
Using the equation above,
ΔHrxn = (2)(-393.5 kJ/mol) + (3)(-285.5 kJ/mol) - (-276 kJ/mol)
ΔHrxn = -1367.5 kJ/mol
<em>Answer: -1367.5 kJ/mol</em>
Are there choices? Because if there are that would help A LOT, but if there are no choices I can give some examples of physical properties, though there are MILLIONS, here are a few :) .
Physical property examples are: color, smell, freezing point, boiling point, melting point, attraction or repulsion to magnets and viscosity and density. If these are not options, please let me know :)
Have a great day, let me know if I can help with anything else, have a great day, and, if you have time, mark brainiest, I would really appreciate it, thanks! :D
The average speed is calculated using the following formula
Where
T = 298 K [room temperature]
m = mass of each molecule of oxygen
mass of one mole of oxygen molecules = 32 g / mol
mass of one molecule of oxygen will be = 
mass of one molecule of oxygen will be = 
putting values
average speed = 
Average speed = 482.19 m / s
average speed = 1735.8 km / h
so approx = 1700 km/h
