Moles of Na2SO4 = conc. x volume(dm3)
= 2 x (2500cm3/1000)
= 5 mol
Mass of Na2SO4 = moles x molar mass
= 5 x ((23 x 2) + 32.1 + (16 x 4))
= 710.5g
Im confused here. Add the rest of the question for me to help you
1) Zn + 2 HCl = ZnCl2 + H2 ( <span>single replacement )
2) </span>2 NaCl + F2 = 2 NaF + Cl2 ( <span>single replacement )
3) </span>2 AlBr3 + 3 K2SO4 = 6 KBr + Al2(SO4)3 ( <span>double replacement )
4) </span>2 K + MgBr2 = 2 KBr + Mg ( <span>single replacement )
Answer 3
hope this helps!</span>
Answer: It is important to wet the filter paper in the Buchner funnel first with cold re crystallization solvent before the re crystallization mixture being filtered to minimize gaps around the edges of the filter paper which can prevent mechanical impurities from passing through. This gives better filtration where most impurities can be filtered. Furthermore, it provides good vacuum.
