Isotopes are variants atoms of the same element, having same number of atomic(proton) number but different number of neutrons and mass number.
Considering iron-60
- The atomic number which also equals the number of protons for the element iron as can be seen on the periodic table is 26
- The name iron-60 also tells us that this particlar isotope's mass number is 60.
- The chemical symbol for Iron is Fe
Now expressing as an isotope iron-60 becomes ⁶⁰₂₆Fe ( very unstable )
Other stable isotopes of Iron include ⁵⁴₂₆Fe , ⁵⁶₂₆Fe, ⁵⁷₂₆Fe and ⁵⁸₂₆Fe
See more here: brainly.com/question/11236150
Answer:
![\frac{[magenta\ phenolphthalein]}{[colorless\ phenolphthalein]}=31.62](https://tex.z-dn.net/?f=%5Cfrac%7B%5Bmagenta%5C%20phenolphthalein%5D%7D%7B%5Bcolorless%5C%20phenolphthalein%5D%7D%3D31.62)
Explanation:
Considering the Henderson- Hasselbalch equation for the calculation of the pH of the buffer solution as:
![pH=pKa+\log\frac{[base]}{[acid]}](https://tex.z-dn.net/?f=pH%3DpKa%2B%5Clog%5Cfrac%7B%5Bbase%5D%7D%7B%5Bacid%5D%7D)
Where Ka is the dissociation constant of the acid.
pKa of phenolphthalein = 9.40
pH = 10.9
So,
![10.9=9.40+\log\frac{[magenta\ phenolphthalein]}{[colorless\ phenolphthalein]}](https://tex.z-dn.net/?f=10.9%3D9.40%2B%5Clog%5Cfrac%7B%5Bmagenta%5C%20phenolphthalein%5D%7D%7B%5Bcolorless%5C%20phenolphthalein%5D%7D)
Correct Answer: Option C
Reason:
<span>The </span>Pauli Exclusion Principle<span> states as '<em>in an atom or molecule, no two electrons can have the same four electronic quantum numbers. Further, an orbital can contain a maximum of only two electrons, the two electrons must have opposing spins.</em>'
</span>
Thus, it can be seen that in option C, electrons in last 2 subshell have electrons with same spin, which is a violation of Pauli Exclusion Principle .
This is a chemical change because there is a new substance that was created and the new chemical can cause other chemical reaction to happen compared to the 1st state of chemical that was in the cave. Because the cave water was exposed to another environment, the calcium bicarbonate, which is also known as salt. When the cave's groundwater was exposed to a different environment the atom in the cave water rearranged and crystallized.
