Answer:
The mass of (NH₄)₂S we may add to the solution is: 1.98 g
Step-by-step explanation:
We interpret the given data:
0.114 m → moles of solute in 1kg of solvent
255 g → the mass of solvent
As we have 0.114 moles of solute ((NH₄)₂S) in 1kg, we must determine the moles in our mass of solvent (255 g H₂O)
We convert the mass of solvent to kg → 255 g . 1 kg/1000g = 0.255 kg
Now we can determine the moles of solute, we used:
0.114 mol/kg . 0.255 kg = 0.02907 moles
If we convert the moles to mass → 0.02907 mol . 68.1g /1mol = 1.98 g