The balanced reaction is
3Na3PO4 + 2CuSO4 ------> 3Na2SO4 + Cu3(PO4)2
To balance this reaction of double displacement, we see first that this reaction maintain the valence numbers of every atom.
Then, to have the same value of Na in the two sides of the reaction we multiply for the number of the other side. So,
(Na3PO4)x 2
(Na2SO4)x3
As we can see either, we need to balance PO4 cause there are two molecules of this in the reactant side, so we have two molecules of PO4 in the product either.
Then we get
3Na3PO4 + 2CuSO4 ------> 3Na2SO4 + Cu3(PO4)2
To probe that balance was correct, you can verify that the charges are exactly the opposite.
This is false, all non metals have different physical properties.
most reactive among them is fluorine because it is the most electronegative element
Answer: at low pressure and high temperature.
The real gases deviate from ideal gases at high pressures and low temperatures, because high pressure and low temperatures reduce the free space between the particles and their velocities, causing that the effect of the volume of the particles of the gas and the intermolecular forces be more important.
The lower the pressure and the higher the temperatures the less the effect of the volume of the particles and of the intermolecular forces. Remember that ideal gas theory considers that individual particles do not occupy space and they do not intereact one to each other (except for the collisions).
