<span>a. 3.1 calories in heat were released by the burning candy bar sample
b. The energy value of the sample was 3.1 Cal/g
c.The total caloric content of the candy bar is 232.5 Calories, derived by multiplying the total mass of the candy bar by its fuel value per gram</span>
Since the forward reaction is endothermic (heat is consumed in the reaction) that means that the enthalpy change for the forward reaction is a positive value.
Therefore, i would say that the reverse or backward reaction is exothermic (heat is released in the reaction to the sorroundings) and that the enthalpy change is a negative value.
Hey there!
The pH of a weak base (in this case, pyridine is a weak base) is calculated by using the weak base equation, and then solving it.
C5H5N; Kb= 1.7 x 10⁻⁹
pH = -log [H⁺]
we can also say that pH = 14 + log [OH⁻]
Plugging into the weak base equation, we know that Kb = [OH⁻][BH⁺] / [B]
This can be solved using an ice chart, which will then simplify to :
Kb = [x][x] / [0.50-x]
We can assume that x is very small in comparison to the 0.5 , so we consider it zero.
Then plug in and solve for x. 1.79 *10-9 = x² / 0.5
x = 2.992 * 10⁻⁵
ince X is equal to the [OH⁻] concentration, we can plug it into the second pH equation, and get the pH!
pH = 14+ log 2.99 * 10⁻⁵
pH = 9.48
Hope that helps!
Answer:
what is the English translation, id like to help
Explanation:
