why an ice cube at 0 ˚C is more effective in cooling a drink than
the same mass of water also at 0 ˚C
nice homework dump, though some of the problems contain out-of-font characters. No ideas on any of them?
An ice cube at 0 ˚C is more effective in cooling a drink than the same mass of water at 0 ˚C due to the difference in the specific heat capacity of ice and water.
To understand this, let's first clarify what specific heat capacity is. Specific heat capacity is the amount of heat energy required to raise the temperature of a substance by a certain amount. It is measured in units of J/(g·°C) or J/(kg·°C).
The specific heat capacity of water is significantly higher than that of ice. Water has a specific heat capacity of approximately 4.18 J/(g·°C), whereas ice has a specific heat capacity of about 2.09 J/(g·°C). This means that it takes about twice as much heat energy to raise the temperature of water compared to ice by the same amount.
When we place an ice cube in a drink, the ice absorbs heat energy from the surrounding liquid to melt into water. This process is called latent heat of fusion. During this phase change, the temperature of the ice remains constant at 0 ˚C until all the ice has melted. Thus, the ice cube effectively cools the drink without significantly raising its temperature.
On the other hand, if we were to use the same mass of water instead of ice, the water would take longer to cool the drink because it requires more heat energy to increase its temperature. Water at 0 ˚C would need to absorb a significant amount of heat energy from the liquid in the drink before it started to warm up. This would result in less effective cooling compared to an ice cube.
In summary, the higher specific heat capacity of water compared to ice means that an ice cube at 0 ˚C can absorb heat energy from the drink more efficiently and provide better cooling.