Passage II
In the periodic table, a column of elements is called a group. For each of 5 elements in Group 2A and for each of 5 elements in Group 3A, Table 1 gives the atomic mass (average mass of 1 atom in atomic mass units, amu) and 3 other properties at a temperature of 298 K:
• density,
• specific heat (amount of heat required to raise the temperature of 1 g of a substance by 1 K),
• thermal conductivity (ability to conduct heat; the greater the thermal conductivity, the more effectively the substance conducts heat).
Figure 1 shows, for Al and for Mg, how the thermal conductivity varies between 1 K and 100 K.
12. Based on Figure 1, at which of the following temperatures is the thermal conductivity of Al closest in value to the thermal conductivity of Mg ?
Your Answer is
Correct Answer is J
Explanation
Looking at Figure 1, the closer the two lines are, the more similar their thermal conductivity is, so when the temperature is closer to 100K, the closer the two lines are, the more similar their thermal conductivity is. So option J is reasonable.