How much heat is needed to change the temperature of 3 grams of gold (c = 0.129 ) from 21°C to 363°C? The answer is expressed to
2 answers:
The correct answer to the question is : B) 132 Joules.
EXPLANATION :
As per the question, the mass of the gold m = 3 gram.
The initial temperature of the gold T = 21 degree celsius.
The final temperature of the gold T' = 363 degree celsius.
Hence, the change in temperature dT = T' - T
= 363 - 21 degree celsius
= 342 degree celsius.
The specific heat of the gold is given as c =
We are asked to calculate the heat required ( dQ ) to raise the temperature of gold.
The heat required for this is calculated as -
dQ = mcDT
= 3 × 342 × 0.129 J
= 132.354 J
≈ 132 J
Hence, the correct answer is 132 J.
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