A 17.5 g sample of metal at 125.0°C is placed in a calorimeter with 15.0 g of water at 25.0°C. if the temperature of the water rises to 30.0°C, what is the specific heat of the metal?

1 Answer
Jul 22, 2016

The specific heat of the meta is C_p = 0.189 J/(g^oC)Cp=0.189JgoC

Explanation:

This is a thermo-equillibrium situation. We can use the equation

Loss of Heat of the Metal = Gain of Heat by the Water

-Q_(m) = +Q_(w)Qm=+Qw

Q = mDeltaTC_pQ=mΔTCp

Q =Q= Heat
m =m= mass
DeltaT = (T_f-T_i)ΔT=(TfTi)
T_f=Tf= Final Temp
T_i=Ti= Initial Temp
C_P=CP= Specific Heat

Metal
Water
m =17.5 gm=17.5g
T_f=30.0^oCTf=30.0oC
T_i=125.0^oCTi=125.0oC
C_P= xCP=x

Water
m =15.0 gm=15.0g
T_f=30.0^oCTf=30.0oC
T_i=25.0^oCTi=25.0oC
C_P= 4.184 J/(g^oC)CP=4.184JgoC#

-Q_(m) = +Q_(w)Qm=+Qw
-[m(T_f-T-i)C_p] = m(T_f-T-i)C_p[m(TfTi)Cp]=m(TfTi)Cp

-[17.5g(30^oC-125^oC)x] = 15g(30^oC-25^oC)4.184J/(g^oC)[17.5g(30oC125oC)x]=15g(30oC25oC)4.184JgoC

-[17.5g(-95^oC)x] = 15cancel(g)(5^ocancelC))4.184J/(cancel(g^oC))

(1662.5g^oC)x = 313.8J

cancel(1662.5g^oC)x/cancel(1662.5g^oC) = (313.8J)/(1662.5g^oC)

C_p = 0.189 J/(g^oC)