Which response lists all the following pairs that are miscible liquids?
Pair #1: octane ($C_8H_{18}$) and water
Pair #2: acetic acid ($CH_3COOH$) and water
Pair #3: octane ($C_8H_{18}$) and carbon tetrachloride ($CCl_4$)
A. 1, 3
B. 1, 2
C. 2, 3
Answer (1)
Octane and water are immiscible because octane is nonpolar and water is polar.
Acetic acid and water are miscible because both are polar.
Octane and carbon tetrachloride are miscible because both are nonpolar.
Therefore, the miscible pairs are 2 and 3, and the answer is 2 , 3 .
Explanation
Analyzing Miscibility Based on Polarity Let's analyze the miscibility of the given pairs of liquids based on their polarity. The principle 'like dissolves like' will guide our analysis.
Pair #1: Octane and Water Pair #1: Octane ( C 8 H 18 ) is a nonpolar hydrocarbon, and water ( H 2 O ) is a polar solvent. Nonpolar and polar liquids are generally immiscible.
Pair #2: Acetic Acid and Water Pair #2: Acetic acid ( C H 3 COO H ) is a polar solvent, and water ( H 2 O ) is also a polar solvent. Polar liquids are generally miscible with other polar liquids.
Pair #3: Octane and Carbon Tetrachloride Pair #3: Octane ( C 8 H 18 ) is a nonpolar hydrocarbon, and carbon tetrachloride ( CC l 4 ) is a nonpolar solvent. Nonpolar liquids are generally miscible with other nonpolar liquids.
Conclusion Therefore, Pair #2 (acetic acid and water) and Pair #3 (octane and carbon tetrachloride) are miscible.
Final Answer The correct response lists all the miscible pairs, which are pairs 2 and 3.
Examples
Understanding miscibility is crucial in many real-world applications. For instance, in the food industry, it helps in creating stable emulsions like salad dressings where oil and vinegar (acetic acid in water) are mixed. Similarly, in the pharmaceutical industry, it's essential for formulating drugs where active ingredients need to dissolve properly in a solvent to ensure effective delivery. In environmental science, understanding why oil spills don't mix with water helps in developing effective cleanup strategies. The principle of 'like dissolves like' is a fundamental concept that underpins these applications, ensuring that mixtures are stable and effective for their intended purposes.
