When varsol and iodine in potassium iodide aqueous solution is mixed, two phases form.
What are the colours in each of the 2 phases when 2ml of I2/KI aqueous solution plus 2 ml of varsol are mixed in a test tube?
What are the colours in each of the 2 phases when each of the following are also added to the test tube containing 2 ml of I2/KI and 2 ml varsol and why:
a) 4 ml varsol
b) 4 ml water
c) 2 drops saturated iodine in KI solution
d) 2 drops saturated sodium thiosulphate
e) 2 drops saturated sodium potassium iodide solution
When varsol and iodine in potassium iodide aqueous solution are mixed, two phases form. The colors in each of the two phases depend on the specific components present and their reactions.
In the case of mixing 2 ml of I2/KI aqueous solution with 2 ml of varsol in a test tube, two phases will form. The colors in each phase will be:
1. Organic Phase (Varsol phase): Since varsol is a clear, colorless liquid, the organic phase will appear colorless.
2. Aqueous Phase (I2/KI phase): The I2/KI (iodine in potassium iodide) aqueous solution is usually brown or reddish-brown in color. Therefore, the aqueous phase will be brown or reddish-brown.
Now, let's go through each additional component and their effects on the colors of the two phases:
a) When 4 ml of varsol is added:
The organic phase (Varsol phase) will remain colorless, but the volume of the organic phase will increase.
b) When 4 ml of water is added:
The aqueous phase (I2/KI phase) may become slightly diluted, but the brown or reddish-brown color should still be present. The organic phase (Varsol phase) will remain colorless.
c) When 2 drops of saturated iodine in KI solution are added:
The addition of saturated iodine in KI solution will increase the amount of iodine in the system. This will likely intensify the brown or reddish-brown color in the aqueous phase (I2/KI phase).
d) When 2 drops of saturated sodium thiosulphate are added:
Sodium thiosulphate is known to react with iodine and can reduce its color. The addition of sodium thiosulphate may cause the brown or reddish-brown color in the aqueous phase (I2/KI phase) to fade or disappear.
e) When 2 drops of saturated sodium potassium iodide solution are added:
Sodium potassium iodide solution is commonly used as an iodine test solution. The addition of this solution may further increase the amount of iodine in the system and intensify the brown or reddish-brown color in the aqueous phase (I2/KI phase). The organic phase (Varsol phase) will remain colorless.
It is important to note that the specific observations may vary slightly depending on the concentrations and specific reactions involved.
To determine the colors in each of the phases when different substances are added to the test tube containing I2/KI aqueous solution and varsol, we need to understand the properties and reactions of these substances.
In this case, varsol is a common name for mineral spirits or white spirit, which is a clear, colorless liquid hydrocarbon solvent. Iodine in potassium iodide (I2/KI) aqueous solution is an orange-brown color. When these two substances are mixed, two phases form due to differences in solubility.
Let's analyze the colors in each of the phases when different substances are added:
a) 4 ml varsol:
Since varsol is already present in the initial mixture, adding more varsol does not change the color of the phases. The two phases formed will retain their original colors, with the top layer being a clear, colorless varsol phase, and the bottom layer being an orange-brown I2/KI aqueous solution phase.
b) 4 ml water:
Adding water to the mixture does not significantly affect the solubility or color of the substances. Again, the two distinct phases will maintain their original colors, with the clear varsol phase on top and the orange-brown I2/KI aqueous solution phase below.
c) 2 drops saturated iodine in KI solution:
Saturated iodine in potassium iodide solution contains excess iodine, which is a dark purple color. When a few drops of this solution are added to the mixture, the color of the bottom phase will change from orange-brown to a darker purple hue. The top varsol phase will remain colorless.
d) 2 drops saturated sodium thiosulphate:
Saturated sodium thiosulphate is known for its ability to react with iodine and reduce its color. When a few drops are added to the mixture, the orange-brown color of the bottom phase will start to fade as the thiosulphate reacts with iodine. Over time, the color may become pale yellow or colorless. The varsol phase will remain colorless.
e) 2 drops saturated sodium potassium iodide solution:
Saturated sodium potassium iodide solution is often used as a source of iodide ions. When added to the mixture, the color of the bottom phase will remain orange-brown, as there is already an excess of iodine present in the I2/KI solution. The top varsol phase will remain colorless.
It's important to note that the colors mentioned are based on the typical behavior of these substances. Actual observations may vary depending on the specific concentrations and conditions of the experiment.