Answer:
Explanation:
First we convert <u>the given masses of each element into moles</u>, using <em>their respective molar masses</em>:
- Fe ⇒ 11.26 g ÷ 55.845 g/mol = 0.202 mol Fe
- S ⇒ 9.70 g ÷ 32.065 g/mol = 0.302 mol S
Now we <em>divide them</em> in order to <u>calculate the molar ratio of S to Fe</u>:
Meaning that for each 1 Fe mol, there's 1.5 S moles. We can write that as Fe₁S₁.₅
Finally we <u>double those subscripts</u> so that <em>they become the lowest possible integers</em>: Fe₂S₃.
Density is sensitive to temperature for gases and liquids, although not much for liquids. We use the data in the picture. Using linear interpolation, we determine the densities at 14°C and 20°C.
@20°C: Density = 0.99823 g/cm³ or g/mL
@14°C:
(10 - 14)/(10 - 20) = (0.99973 - Density)/(0.99973 - 0.99823)
Solving for density:
Density = 0.99913 g/cm³ or g/mL
Mass @ 20°C = 50 mL * 0.99823 g/mL = 49.9115 g
Mass @ 14°C = 50 mL * 0.99913 g/mL = 49.9565 g
Difference of Masses = |49.9115 g - 49.9565 g| = 0.045 g