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Question
A constant-volume thermometer registers a pressure of 1.500 × 104 Pa at the triple point of water and a pressure of 2.050 × 104 Pa at the normal boiling point. What is the temperature at the normal boiling point?
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Solution
Given:
Pressure registered by a constant-volume thermometer at the triple point, Ptr = 1.500 × 104 Pa
Pressure registered by the thermometer at the normal boiling point, P = 2.050 × 104 Pa
We know that for a constant-volume gas thermometer, temperature (T) at the normal boiling point is given as:
T`=P/P_(tr) × 273.16 K`
`=> T = (2.050 × 10^4)/1.500 × 10 ^ 4 × 273.16 K`
⇒ T = 373.31 K
Therefore, the temperature at the normal point (T) is 373.31 K.
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