<span>1 mole of benzene (78g) requires 30.8 kJ/ of heat, so 11.5g will need ..... (it's a proportion calculation.) Temperature does not change at BPt and is not relevant if the temp of the liquid is already at the BPt
ne definition of entropy is qrev/T, where qrev is the heat added in reversible operation (for complicated reasons pertaining to heat as a path function) and T is the temperature at which this is done.
Phase changes are particularly good examples for calculations of changes in entropy, since temperature will not change will the bonds of a state are being broken.
The calculations required boils down to:
1) finding the moles of benzene given from molar mass.
2) multiplying that moles by the heat of vaporization.
3)diving the heat energy required by the temperature of boiling point.</span>
The student needs to dilute the stock to get the proper concentration. And during the dilution, the molar number of solute will not change. So the volume of stock needed is 2*0.1/1.75=0.114 L. Then dilute to 2.00 L.
Answer:
Q = -22.9 kJ
Explanation:
Given that,
Mass of water, m = 150.3 g
Water gets cool from 25.60°C to -10.70°C.
The specific heat of water, c = 4.2 J/g°C
The formula for heat needed is given by :

So, 22.9 kJ of heat is needed to be removed to cool.
C a solution because salt is a solute