Answer:
t = 20.74 sec
Explanation:
Using integrated rate law for first order kinetics as:
![[A_t] =[A_0] -kt](https://tex.z-dn.net/?f=%5BA_t%5D%20%3D%5BA_0%5D%20-kt)
Where,
![[A_t]](https://tex.z-dn.net/?f=%5BA_t%5D)
is the concentration at time t = 0.220 M
![[A_0]](https://tex.z-dn.net/?f=%5BA_0%5D)
is the initial concentration = 0.780 M
k is the rate constant = 0.0270 M s⁻¹
So,
<u>t = 20.74 sec</u>
Answer:
Va = (MbVb)/Ma
Explanation:
Divide both sides by Ma and voila!
I found the answer online.
Alright, so this question covers the subject of spontaneous reactions. Reactions tend to be spontaneous if the products have a lower potential energy than the reactants or when the product molecules are less ordered than the reactant molecules. This may seem a little confusing but to put it simply, spontaneous reactions occur naturally.
This means there is no external force for the reaction, usually exothermic, and increases entropy. Gibbs free energy change helps us determine if the reaction is spontaneous:
delta G= delta H -T(delta S) spontaneous if delta G<0
Remember that H stands for enthalpy, or potential energy; T is for temperature; and S is entropy, the amount of disorder(spontaneous reactions increase in entropy take for ice to liquid water).
- delta H= exothermic
The reaction in the problem releases heat so the enthalpy is negative.
delta S increases with increased temperature
The entropy will be positive.
Plugging this in the Gibbs equation, you can assume delta G will be less than 0.
Therefore, the answer is B. Sorry for the long and possibly not helpful explanation. I'm learning this material currently myself. Best of luck!
