The correct answer would be the first option. Material A having a smaller latent heat of fusion would mean that it will take only less energy to phase change into the liquid phase. Latent of heat of fusion is the amount of energy needed of a substance to phase change from solid to liquid or liquid to solid.
Answer:
the change is evaporation
Explanation:
the water heats up at the surface of the water and evaporates
To determine the time it takes to completely vaporize the given amount of water, we first determine the total heat that is being absorbed from the process. To do this, we need information on the latent heat of vaporization of water. This heat is being absorbed by the process of phase change without any change in the temperature of the system. For water, it is equal to 40.8 kJ / mol.
Total heat = 40.8 kJ / mol ( 1.50 mol ) = 61.2 kJ of heat is to be absorbed
Given the constant rate of 19.0 J/s supply of energy to the system, we determine the time as follows:
Time = 61.2 kJ ( 1000 J / 1 kJ ) / 19.0 J/s = 3221.05 s
Answer:
ΔG°rxn = -72.9 kJ
Explanation:
Let's consider the following reaction.
HCN(g) + 2 H₂(g) → CH₃NH₂(g)
We can calculate the standard Gibbs free energy of the reaction (ΔG°rxn) using the following expression:
ΔG°rxn = ΔH° - T.ΔS°
where,
ΔH° is the standard enthalpy of the reaction
T is the absolute temperature
ΔS° is the standard entropy of the reaction
ΔG°rxn = -158.0 KJ - 387 K × (-219.9 × 10⁻³ J/K)
ΔG°rxn = -72.9 kJ
Answer:
The molar mass of the protein is 12982.8 g/mol.
Explanation:
The osmptic pressure is given by:
π=MRT
Where,
M: is molarity of the solution
R: the ideal gas constant (0.0821 L·atm/mol·K)
T: the temperature in kelvins
Hence, we look for molarity:
= =5.584×10⁻³mol/l
As we have 2 ml of solution, we can get the moles quantity:
Moles of protein: 5.584×10⁻³
×2ml=1.117×10⁻⁵mol
Finally, the moles quantity is the division between the mass of the protein and the molar mass of the protein, so:
Moles=Mass/Molar mass
Molar mass= Mass/Moles=
=12982.8 g/mol
