AH1 = m * c1 * AT1 calculate this for ice (-25C to 0C) AH2 = AHfus(1 mole)=6.01 kJ = 6010 J AH3 = m *c3 * AT3 calculat this for water (0C to 100C) AH4 = AHvap(1mole)=40.67 kJ = 40670 J AH5= m * c5 * AT5 calculate this for steam (100C to 125C)
Sum ---- AH1+AH2+AH3+AH4+AH5
Data m=18g (1mole water)
c1=specific heat ice= 2.09 J/g K c3=specific heat water= 4.18 J/g K c5=specific heat steam= 1.84 J/g K
AT = (Tend - Tinitial) as this is a difference between temperatures it doesn't matter the units Celsius or Kelvin. Kelvin (K)=Celsius (C)+273.15
AT1 = 0C - (-25C)= 25C= 273.15K - 248.15K= 25K AT3= 100C - 0C = 100C= 100K AT5= 125C - 100C= 25C=25K
The amount of heat lost by granite is equal to the amount
of heat gained by water. Therefore their change in enthalpies must be equal.
The opposite in sign means that one is gaining while the other is losing
ΔH granite = - ΔH water
ΔH is the change in enthalpy experienced by a closed object
as it undergoes change in energy. This is expressed mathematically as,
ΔH = m Cp (T2 – T1)
Given this information, we can say that:
12.5 g * 0.790 J / g ˚C * (T2 – 82 ˚C) =
- 25.0 g * 4.18 J / g ˚C
* (T2 – 22 ˚C)
9.875 (T2 – 82) = 104.5 (22 – T2)
9.875 T2 – 809.75 = 2299 – 104.5 T2
114.375 T2 = 3108.75
T2 = 27.18 ˚C
The temperature of 2 objects after reaching thermal
equilibrium is 27.18 ˚<span>C.</span>
you calculate all the letters together and it would be Zn2
