What is the mass of lead if, when it is cooled from the crystallization temperature to 27C, an amount of heat of 156000 J is released?
To calculate the value of the mass of cooled lead, we apply the formula: Q = Cc * m * (tcr – tc), whence we express: m = Q / (Cc * (tcr – tc)).
Variables and constants: Q – released heat (Q = 156000 J); Сс – specific heat (Сс = 140 J / (kg * K)); tcr – crystallization temperature (tcr = 327.4 ºС ≈ 327 ºС); tк – final temperature (tк = 27 ºС).
Calculation: m = Q / (Cc * (tcr – tc)) = 156000 / (140 * (327 – 27)) = 3.71 kg.
Answer: The mass of cooled lead is 3.71 kg.
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