A) i believe the reaction is exothermic, because 27.6 kg of thermal energy is gained by the water solution, the dissolution of urea is exothermic. Exothermic reaction is a chemical reaction that releases energy by light or heat. It is the opposite of an endothermic reaction where heat is gained by the reaction.
b) The water gained the heat released when urea dissolve. That is the water gained 27.6 kJ, while dissolution of urea released 27.6 kJ. Therefore, the heat gained is equal to the heat lost.
c) From part B, since heat gained is equal to heal lost, then
250 g × (Tf -30) ×4.18 J/g = 27600 J
= 1045 Tf - 31350J = 27600 J
Tf = 56.41°C.
Therefore the final temperature of the solution is 56.41°C
d) The initial and final temperature in Fahrenheit
°F = °C × (9/5) +32,
Thus, 30°C will be equal to 86° F
while 56.41 will be equivalent to 133.54 ° F
Answer:
The kinetic energy of the translational motion of an ideal gas depends on its temperature.
Explanation:
From the statement of Hess' law, the enthalpy of the reaction A---> C is +90 kJ
<h3>What is Hess' law?</h3>
Hess' law of constant heat summation states that for a multistep reaction, the standard enthalpy of reaction is always constant and is independent of the pathway or intermediate routes taken.
From Hess' law, the enthalpy change for the reaction A ----> C is calculated as follows:
A---> C = A ---> B + B ---> C
ΔH of A---> C = 30 kJ + 60 kJ
ΔH = 90 kJ
Therefore, the enthalpy of the reaction A---> C is +90 kJ
The above reaction A---> C can be shown in the enthalpy diagram below:
A -------------------> C (ΔH = +90 kJ)
\ /
\ / (ΔH = +60 kJ)
(ΔH = +30 J) \ /
> B
Learn more about enthalpy and Hess law at: brainly.com/question/9328637
Mechanical twinning occurs in metals having body center cubic and hexagonal closed packed structures. Twinning is said to occur when a portion of a crystal takes up an orientation that is related to the orientation of the untwinned lattice in a definite symmetrical manner.