Answer:
THE NEW VOLUME OF THE OXYGEN GAS AT 28 PSI FROM 72.5 PSI IS 0.078 L.
Explanation:
Initial volume of the oxygen in the container = 30.0 mL = 30 / 000 L = 0.03 L
Initial pressure of the oxygen = 72.5 psi = 1 psi = 6890 pascal
Final pressure = 28 psi
Final volume = unknown
First convert the mL to L and since both pressures are in similar unit that is psi; there is no need converting them to pascal or other standard unit of pressure. They cancel each other out.
This question follows Boyle's equation of gas laws and mathematically it is written as:
P1 V1 = P2 V2
Re-arranging by making P2 the subject of the formula, we have:
V2 = P1 V1 / P2
V2 = 72,5 * 0.03 / 28
V2 = 2.175 /28
V2 = 0.0776 L
The new volume of the oxygen gas at a change in pressure from 72.5 psi to 28 psi is 0.078 L.
A) covert 0.330g to moles by dividing by molar mass of P2O5 .. Let's call this Y moles
B) 1 mole of anything contains the Avogradro Number of molecules
So here it is 6.02 x 10^23 x Y molecules
C) work out how many atoms in each molecule 2P + 5O total 7
So multiply answer to B by 7 to get final answer
Molecule
The smallest unit in a compound is its molecule.
Force is a pull or a push acting on a body at rest or in motion resulting from its interaction with another body. Input force is the force that you put on a machine while Output force is the force the machine exerts on an object. The output distance is when the output force moves the machine a certain distance while the input distance is when the input distance is when the input force moves the machine a certain distance.
Example :

If you use the subscript (aq) (=aquaris) , this means that the substance is in a solution.
Subscripts:
-aq-this means that the substance is in a solution
-s-this means that the substance is a solid(or precipitate)
-l-this means that the substance is a liquid
-g-this means that the subtance is a gas