To solve this question, we need to identify the chemical formula of the blue-colored copper sulfate crystal.
1. Understanding Copper Sulfate Crystals:
- Copper sulfate (CuSO₄) can form hydrated crystals, which are blue in color. The blue color is due to the presence of water molecules in the crystal structure.
2. Identifying the Correct Hydrate:
- The blue-colored copper sulfate crystals are typically in the form of CuSO₄·5H₂O, known as copper sulfate pentahydrate.
3. Analyzing the Options:
- Option (A) CuSO₄·H₂O: This represents copper sulfate monohydrate, which is not blue in color.
- Option (B) CuSO₄·2H₂O: Represents copper sulfate dihydrate, which is not blue.
- Option (C) CuSO₄·5H₂O: This is the correct formula for blue copper sulfate crystals (copper sulfate pentahydrate).
- Option (D) CuSO₄·10H₂O: This is not correct for the blue-colored copper sulfate.
Final Answer:
Option (C) CuSO₄·5H₂O is correct.
Which element of the 3d series has the lowest enthalpy of atomisation and why?
Methanol is produced by the reversible, gas-phase hydrogenation of carbon monoxide: \[ {CO} + 2{H}_2 \rightleftharpoons {CH}_3{OH} \] CO and H$_2$ are charged to a reactor, and the reaction proceeds to equilibrium at 453 K and 2 atm. The reaction equilibrium constant, which depends only on the temperature, is 1.68 at the reaction conditions. The mole fraction of H$_2$ in the product is 0.4. Assuming ideal gas behavior, the mole fraction of methanol in the product is ____________ (rounded off to 2 decimal places).
The residence-time distribution (RTD) function of a reactor (in min−1) is:
\[ E(t) = \begin{cases} 1 - 2t, & \text{if } t \leq 0.5\ \text{min} \\ 0, & \text{if } t > 0.5\ \text{min} \end{cases} \]
The mean residence time of the reactor is _____ min (rounded off to 2 decimal places).
Oil is extracted from mustard seeds having 20 wt% oil and 80 wt% solids, using hexane as a solvent. After extraction, the hexane-free residual cake contains 1 wt% oil. Assuming negligible dissolution of cake in hexane, the percentage oil recovery in hexane is ___________ % (rounded off to the nearest integer).