Question

In the laboratory a student uses a "coffee cup" calorimeter to determine the specific heat of a metal.

She heats 19.5 grams of tungsten to 97.80°C and then drops it into a cup containing 78.3 grams of water at 22.58°C. She measures the final temperature to be 23.20°C.

Assuming that all of the heat is transferred to the water, she calculates the specific heat of tungsten to be J/g°C.

Answer 1

Answer : The specific heat of tungsten is,
`0.139J/g^oC`

Explanation :

In this problem we assumed that heat given by the hot body is equal to the heat taken by the cold body.

`q_1=-q_2`

`m_1* c_1* (T_f-T_1)=-m_2* c_2* (T_f-T_2)`

where,

`c_1` = specific heat of tungsten = ?

`c_2` = specific heat of water =
`4.18J/g^oC`

`m_1` = mass of tungsten = 19.5 g

`m_2` = mass of water = 78.5 g

`T_f` = final temperature =
`23.20^oC`

`T_1` = initial temperature of tungsten =
`97.80^oC`

`T_2` = initial temperature of water =
`22.58^oC`

Now put all the given values in the above formula, we get

`19.5g* c_1* (23.20-97.80)^oC=-78.5g* 4.18J/g^oC* (23.20-22.58)^oC`

`c_1=0.139J/g^oC`

Therefore, the specific heat of tungsten is,
`0.139J/g^oC`