Answer:
A:temperature
Explanation:
The temperature cannot be determined by looking at the spectra of the star due to lack of the equipment for its measurement. <em>On the other-hand, the remaining statements like the distance from earth, movement towards or away from earth can be determined.</em>
The question is incomplete, the complete question is shown in the image attached.
Answer:
7.69%
Explanation:
The balanced equation of this reaction is shown in the image attached to this answer.
The reaction is redox because we can notice a change in the oxidation number of species from left to right in the reaction equation.
For instance, the oxidation number of oxygen was changed from -1 in H2O2 to zero in O2. Hence H2O2 was oxidized.
To calculate the percentage of H2O2 in the sample;
number of moles of KMnO4 = 137 ml/1000 * 0.230 M = 0.03151 moles of KMnO4
From the reaction equation;
2 moles of permanganate reacts with 5 moles of H2O2
0.03151 moles of permanganate reacts with 0.03151 moles * 5/2 = 0.079 moles of H202
Mass of H2O2 reacted = 0.079 moles of H202 * 34 gmol-1 = 2.69 g
Hence % by mass of H2O2 in the sample = 2.69 g/35 g * 100 = 7.69%
Answer:
I'm pretty sure that it gains 2 electrons
Answer:
0.6749 M is the concentration of B after 50 minutes.
Explanation:
A → B
Half life of the reaction = ![t_{1/2}=25 minutes](https://tex.z-dn.net/?f=t_%7B1%2F2%7D%3D25%20minutes)
Rate constant of the reaction = k
For first order reaction, half life and half life are related by:
![k=\frac{0.693}{t_{1/2}}](https://tex.z-dn.net/?f=k%3D%5Cfrac%7B0.693%7D%7Bt_%7B1%2F2%7D%7D)
![k=\frac{0.693}{25 min}=0.02772 min^{-1}](https://tex.z-dn.net/?f=k%3D%5Cfrac%7B0.693%7D%7B25%20min%7D%3D0.02772%20min%5E%7B-1%7D)
Initial concentration of A = ![[A]_o=0.900 M](https://tex.z-dn.net/?f=%5BA%5D_o%3D0.900%20M)
Final concentration of A after 50 minutes = ![[A]=?](https://tex.z-dn.net/?f=%5BA%5D%3D%3F)
t = 50 minute
![[A]=[A]_o\times e^{-kt}](https://tex.z-dn.net/?f=%5BA%5D%3D%5BA%5D_o%5Ctimes%20e%5E%7B-kt%7D)
![[A]=0.900 M\times e^{-0.02772 min^{-1}\times 50 minutes}](https://tex.z-dn.net/?f=%5BA%5D%3D0.900%20M%5Ctimes%20e%5E%7B-0.02772%20min%5E%7B-1%7D%5Ctimes%2050%20minutes%7D)
[A] = 0.2251 M
The concentration of A after 50 minutes = 0.2251 M
The concentration of B after 50 minutes = 0.900 M - 0.2251 M = 0.6749 M
0.6749 M is the concentration of B after 50 minutes.
Answer:
C Is The Correct Answer Because The Deeper The Rock Is The Older It Is So The Top Is The Youngest And The Bottem Is The Oldest