Answer:
To find the number of Na2SO4 formula units in 1.75 moles of Na2SO4, we first need to determine the Avogadro's number (6.022 x 10^23), which is the number of particles (atoms, molecules, or formula units) in one mole of a substance.
Then we can use the following formula:
Number of formula units = moles of substance x Avogadro's number
Substituting the given values, we get:
Number of formula units = 1.75 moles x 6.022 x 10^23 formula units/mole
Number of formula units = 1.0545 x 10^24 formula units
Therefore, there are approximately 1.0545 x 10^24 Na2SO4 formula units in 1.75 moles of Na2SO4.