Explanation:
-Filter help — delete some big unreacted, undesirable species (norit is probably from what you are sorting through, its only carbon which cleans up things)
— extract with DCM because you are probably in an aqueous phase, and some butanoate is in it
- Anhydrous sodium absorbs excess of water (dries the material)
-evaporation in the hood to clear the DCM and crystallize the product.
Answer is: formula of the complex is [Cr(NH₃)₂(SCN)₄<span>]</span>⁻<span>.
This complex has negative charge (-1) because chromium (central atom or metal) has oxidation number +3, first ligand ammonia has neutral charge and second ligand thiocyanate has negative oxidation number -1:
+3 + 2</span>·0 + 4·(-1) = -1.
(a) One form of the Clausius-Clapeyron equation is
ln(P₂/P₁) = (ΔHv/R) * (1/T₁ - 1/T₂); where in this case:
Solving for ΔHv:
- ΔHv = R * ln(P₂/P₁) / (1/T₁ - 1/T₂)
- ΔHv = 8.31 J/molK * ln(5.3/1.3) / (1/358.96 - 1/392.46)
(b) <em>Normal boiling point means</em> that P = 1 atm = 101.325 kPa. We use the same formula, using the same values for P₁ and T₁, and replacing P₂ with atmosferic pressure, <u>solving for T₂</u>:
- ln(P₂/P₁) = (ΔHv/R) * (1/T₁ - 1/T₂)
- 1/T₂ = 1/T₁ - [ ln(P₂/P₁) / (ΔHv/R) ]
- 1/T₂ = 1/358.96 K - [ ln(101.325/1.3) / (49111.12/8.31) ]
(c)<em> The enthalpy of vaporization</em> was calculated in part (a), and it does not vary depending on temperature, meaning <u>that at the boiling point the enthalpy of vaporization ΔHv is still 49111.12 J/molK</u>.
