Question

Choose the correct statement from the following:
(A). Water has highest density at 4°C
(B). Freezing point of water is 0°C
(C) An Ice cube does not completely dip in water, rather floats on water in a glass.
(D). Addition of common salt reduces freezing point of water.
Choose the correct answer from the options given below:

• A. (A), (B) and (D) only.
• B. (B), (C) and (D) only.
• C. (A), (B), (C) and (D).
• D. (A), (B) and (C) only.

Hint:

The anomalous expansion of water (highest density at 4°C) is a crucial concept. It explains why ice floats, which is essential for aquatic life to survive in frozen lakes during winter.

Answer 1

The Correct Option is C

Step 1: Understand the Concept:
The task is to evaluate the accuracy of four common assertions regarding water's physical properties.
Step 2: Detailed Explanation:
- (A) Water's maximum density occurs at 4°C: This is a characteristic anomaly of water. Water gains density as it cools to 4°C, beyond which it expands and becomes less dense. This statement is accurate.
- (B) Water freezes at 0°C: The freezing point of pure water at standard atmospheric pressure is defined as 0 degrees Celsius (equivalent to 32 degrees Fahrenheit). This statement is accurate.
- (C) An ice cube ... floats on water in a glass: Ice is less dense than liquid water (due to the property noted in A). According to Archimedes' principle, an object less dense than the surrounding fluid will float. This statement is accurate.
- (D) Adding common salt lowers water's freezing point: This phenomenon is known as freezing point depression. The dissolution of a solute, such as salt (NaCl), in a solvent (water) decreases the temperature at which the solution solidifies. This is the principle behind using salt to de-ice roads. This statement is accurate.
Step 3: Final Answer:
As all four statements (A), (B), (C), and (D) are accurate, the correct selection must include all of them.