Sandstone, a sedimentary rock, turns into quartzite, a metamorphic rock, through metamorphosis. Metamorphosis is the use of extreme heat and pressure to change the crystalline structure of a rock or crystal.
Answer:
c
Explanation:
it makes sense and the diagram is build like that with high tech
Explanation: Hydrogen bonds are the strongest one of the intermolecular forces. A hydrogen bond is a bond between hydrogen in one molecule or the other ones are fluorine and nitrogen. So it's between a hydrogen in one molecule and an electronegative atom in another molecule. So they always involve hydrogen.
<u>Answer:</u> The above reaction is non-spontaneous.
<u>Explanation:</u>
For the given chemical reaction:
![Ni^{2+}(aq.)+2Fe^{2+}(aq.)\rightarrow 2Fe^{3+}(aq.)+Ni(s)](https://tex.z-dn.net/?f=Ni%5E%7B2%2B%7D%28aq.%29%2B2Fe%5E%7B2%2B%7D%28aq.%29%5Crightarrow%202Fe%5E%7B3%2B%7D%28aq.%29%2BNi%28s%29)
Here, nickel is getting reduced because it is gaining electrons and iron is getting oxidized because it is loosing electrons.
We know that:
![E^o_{(Fe^{3+}/Fe^{2+})}=0.77V\\E^o_{(Ni^{2+}/Ni)}=-0.23V](https://tex.z-dn.net/?f=E%5Eo_%7B%28Fe%5E%7B3%2B%7D%2FFe%5E%7B2%2B%7D%29%7D%3D0.77V%5C%5CE%5Eo_%7B%28Ni%5E%7B2%2B%7D%2FNi%29%7D%3D-0.23V)
Substance getting oxidized always act as anode and the one getting reduced always act as cathode.
To calculate the
of the reaction, we use the equation:
![E^o_{cell}=E^o_{cathode}-E^o_{anode}](https://tex.z-dn.net/?f=E%5Eo_%7Bcell%7D%3DE%5Eo_%7Bcathode%7D-E%5Eo_%7Banode%7D)
![E^o_{cell}=-0.23-0.77=-1.0V](https://tex.z-dn.net/?f=E%5Eo_%7Bcell%7D%3D-0.23-0.77%3D-1.0V)
Relationship between standard Gibbs free energy and standard electrode potential follows:
![\Delta G^o=-nFE^o_{cell}](https://tex.z-dn.net/?f=%5CDelta%20G%5Eo%3D-nFE%5Eo_%7Bcell%7D)
As, the standard electrode potential of the cell is coming out to be negative for the above cell. Thus, the standard Gibbs free energy change of the reaction will become positive making the reaction non-spontaneous.
Hence, the above reaction is non-spontaneous.