Ideally, when a thermometer is used to measure the temperature of an object, the

Question

Ideally, when a thermometer is used to measure the temperature of an object, the temperature of the object itself should not change.   However, if a significant amount of heat flows from the object to the thermometer, the temperature will change.  A thermometer has a mass of 31.0 g, a specific heat capacity of c = 815 J/(kg

Ideally, when a thermometer is used to measure the temperature of an object, the temperature of the object itself should not change. However, if a significant amount of heat flows from the object to the thermometer, the temperature will change. A thermometer has a mass of 31.0 g, a specific heat capacity of c = 815 J/(kg · C degree ), and a temperature of 12.0 degree C. It is immersed in 119 g of water, and the final temperature of the water and thermometer is 39.2 degree C. What was the temperature of the water before the insertion of the thermometer? (See Table 12.2 for appropriate constants.)

Explanation / Answer

We know that Q=mcT where Q is heat, m is mass, c is heat capacityand T is change in temperature. We can calculate the heat transferred to the thermometer by inserting the data:

We must convert 31g to 0.031kg
Q=(0.031)(815)(39.2-12)
Q=687.208

We know that the heat had to come from somewhere, the water, therefore we can solve for the temperature. We know that the heat capacity of water is 4186 J/kg C. Therefore:
Q=mcT
Q/mc=T

T is a change in temperature, therefore T=(t-39.2)

t-39.2=687.208/((0.0119)(4186)
t-39.2=13.795
t=52.995 degrees C

Related Questions

Navigate

• Browse (All)
• Browse I
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.