To get the ∆S of the reaction, we simply have to add the ∆S of the reactants and the ∆S of the products. Then, we get the difference between the ∆S of the products and the ∆S of the products. If the <span>∆S is negative, then the reaction spontaneous. If the otherwise, the reaction is not spontaneous.</span>
Answer:
![\boxed{\text{1.81 da}}](https://tex.z-dn.net/?f=%5Cboxed%7B%5Ctext%7B1.81%20da%7D%7D)
Explanation:
1. Calculate the decay constant
The integrated rate law for radioactive decay is 1
![\ln\dfrac{A_{0}}{A_{t}} = kt](https://tex.z-dn.net/?f=%5Cln%5Cdfrac%7BA_%7B0%7D%7D%7BA_%7Bt%7D%7D%20%3D%20kt)
where
A₀ and A_t are the counts at t = 0 and t
k is the radioactive decay constant
![\ln \dfrac{846}{269} = k \times 3.00\\\\\ln3.145 = 3.00k\\1.146 = 3.00k\\\\k =\dfrac{1.146}{3}\\\\k = \text{0.382 /da}\\](https://tex.z-dn.net/?f=%5Cln%20%5Cdfrac%7B846%7D%7B269%7D%20%3D%20k%20%5Ctimes%203.00%5C%5C%5C%5C%5Cln3.145%20%3D%203.00k%5C%5C1.146%20%3D%203.00k%5C%5C%5C%5Ck%20%3D%5Cdfrac%7B1.146%7D%7B3%7D%5C%5C%5C%5Ck%20%3D%20%5Ctext%7B0.382%20%2Fda%7D%5C%5C)
2. Calculate the half-life
![t_{\frac{1}{2}} = \dfrac{\ln2}{k} = \dfrac{\ln2}{0.382} = \text{1.81 da}](https://tex.z-dn.net/?f=t_%7B%5Cfrac%7B1%7D%7B2%7D%7D%20%3D%20%5Cdfrac%7B%5Cln2%7D%7Bk%7D%20%3D%20%5Cdfrac%7B%5Cln2%7D%7B0.382%7D%20%3D%20%5Ctext%7B1.81%20da%7D)
The half-life for decay is
.
Answer:
Acid solution
Explanation:
In acid-base titrations carried out in school and college labs, many of the older generation, well-informed teachers told their students that the acid solution should be taken in the burette.
Answer:
Creo que la respuesta es n. Transalation : I think the answer is N.
Explanation:
Answer: The total energy, in kilojoules, that is needed to turn a 46 g block of ice at -25 degrees C into water vapor at 100 degrees C is 11.787 kJ.
Explanation:
Given: Mass = 46 g
Initial temperature = ![-25^{o}C](https://tex.z-dn.net/?f=-25%5E%7Bo%7DC)
Final temperature = ![100^{o}C](https://tex.z-dn.net/?f=100%5E%7Bo%7DC)
Specific heat capacity of ice = 2.05 ![J/g^{o}C](https://tex.z-dn.net/?f=J%2Fg%5E%7Bo%7DC)
Formula used to calculate the energy is as follows.
![q = m \times C \times (T_{2} - T_{1})](https://tex.z-dn.net/?f=q%20%3D%20m%20%5Ctimes%20C%20%5Ctimes%20%28T_%7B2%7D%20-%20T_%7B1%7D%29)
where,
q = heat energy
m = mass
C = specific heat capacity
= initial temperature
= final temperature
Substitute the values into above formula as follows.
![q = m \times C \times (T_{2} - T_{1})\\= 46 g \times 2.05 J/g^{o}C \times (100 - (-25))^{o}C\\= 11787.5 J (1 J = 0.001 kJ)\\= 11.787 kJ](https://tex.z-dn.net/?f=q%20%3D%20m%20%5Ctimes%20C%20%5Ctimes%20%28T_%7B2%7D%20-%20T_%7B1%7D%29%5C%5C%3D%2046%20g%20%5Ctimes%202.05%20J%2Fg%5E%7Bo%7DC%20%5Ctimes%20%28100%20-%20%28-25%29%29%5E%7Bo%7DC%5C%5C%3D%2011787.5%20J%20%281%20J%20%3D%200.001%20kJ%29%5C%5C%3D%2011.787%20kJ)
Thus, we can conclude that the total energy, in kilojoules, that is needed to turn a 46 g block of ice at -25 degrees C into water vapor at 100 degrees C is 11.787 kJ.