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Substances a and b are the same mass and at the same initial temperature. when they are heated, the final temperature of a is 55.0oc higher than the temperature of b. what does this tell you about the specific heats of a and b?

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Final answer:

The higher final temperature of substance A compared to substance B, despite both having the same mass and initial temperature, indicates that substance A has a lower specific heat. This is deduced from the formula Q = mcΔT, where specific heat (c) is inversely related to the temperature change (ΔT) for a given amount of heat (Q).

Step-by-step explanation:

When substances A and B, of the same mass and initial temperature, are heated and substance A's final temperature is 55.0 °C higher than that of substance B, it indicates a difference in their specific heats. The specific heat of a substance is defined as the amount of heat required to change the temperature of a unit mass of the substance by 1.00 °C. Because equal masses of A and B received the same amount of heat and A's temperature increased more, we can conclude that A has a lower specific heat than B.

This is based on the formula Q = mcΔT, where Q represents the heat added, m is mass, c is the specific heat, and ΔT is the temperature change. To find the specific heat (c) of a substance, we can rearrange this formula to: c = Q / (mΔT). For example, if a piece of unknown solid substance weighing 437.2 g requires 8460 J to increase its temperature from 19.3 °C to 68.9 °C, the specific heat can be calculated using the mentioned formula, leading to a potential identification if matched with known values from a reference table like Table 9.1.

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