The chart shows the specific heat capacities for four substances at 25°C.
Substance Specific heat (J/g°C)
air 1.020
copper 0.385
glass 0.840
iron 0.444
Javier is designing a container to hold cold items. Which substance should Javier use to best insulate the container?
A
air, because it requires a lot of energy for air to change temperatures
B
copper, because if requires very little energy for copper to change temperatures
C
glass, because it requires a lot of energy for glass to change temperatures
D
iron, because it requires a very little energy for iron to change temperatures
A) air, because it requires a lot of energy for air to change temperatures
The correct answer is A. Javier should use air to best insulate the container. Air has a specific heat capacity of 1.020 J/g°C, which means it requires a lot of energy for air to change temperatures. This property makes air an effective insulation material as it is less likely to transfer heat and keeps the temperature inside the container more constant.
To determine which substance would best insulate the container, we need to consider their specific heat capacities. The specific heat capacity measures the amount of energy required to change the temperature of a substance.
In this case, we want a substance with a high specific heat capacity. This means that it would require a lot of energy to change the temperature of the substance. The higher the specific heat capacity, the better the substance is at retaining its temperature and insulating against temperature changes.
Looking at the options provided:
A) Air has a specific heat capacity of 1.020 J/g°C.
B) Copper has a specific heat capacity of 0.385 J/g°C.
C) Glass has a specific heat capacity of 0.840 J/g°C.
D) Iron has a specific heat capacity of 0.444 J/g°C.
Comparing the values, air has the highest specific heat capacity among the given substances. This means that air requires the most energy to change its temperature, making it the best insulator among the options provided.
Therefore, Javier should use air to best insulate the container (option A).