At which temperature does liquid water show maximum density?

Correct option is B

The correct answer is (b) 277 K.
Explanation: Water exhibits its maximum density at 277 K, which is equivalent to 4°C. At this temperature, water molecules are most closely packed, meaning it has the greatest density. Below 4°C, water begins to expand due to the formation of a crystalline structure as it approaches freezing, which is why ice floats on liquid water. This unique property of water, known as anomalous expansion, is essential for aquatic life in cold environments since it allows water to remain liquid below the ice layer.
Information Booster:
● Maximum Density Temperature: Water is densest at 277 K (4°C). ● Anomalous Expansion: Water expands below 4°C, making ice less dense than liquid water. ● Implications for Ecosystems: This property allows ice to form on top of lakes, insulating the water beneath and protecting aquatic life in winter. ● Density and Temperature Relationship: Water’s density increases as it cools to 4°C, then decreases upon further cooling.