Answer : The concentration of
needed is, 
Explanation :
First we have to calculate the mole of phosphate.
As we are given that, 1 mg P/L that means, 1 mg of phosphate present in 1 L of solution.

Molar mass of phosphate = 94.97 g/mole

Now we have to calculate the concentration of phosphate.


Now we have to calculate the concentration of
.
The second equilibrium reaction is,

The solubility constant expression for this reaction is:
![K_{sp}=[Fe^{3+}][PO_4^{3-}]](https://tex.z-dn.net/?f=K_%7Bsp%7D%3D%5BFe%5E%7B3%2B%7D%5D%5BPO_4%5E%7B3-%7D%5D)
Given: 
![\frac{1}{4}=[Fe^{3+}]\times 1.053\times 10^{-5}mol/L](https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7B4%7D%3D%5BFe%5E%7B3%2B%7D%5D%5Ctimes%201.053%5Ctimes%2010%5E%7B-5%7Dmol%2FL)
![[Fe^{3+}]=2.37\times 10^4M](https://tex.z-dn.net/?f=%5BFe%5E%7B3%2B%7D%5D%3D2.37%5Ctimes%2010%5E4M)
Thus, the concentration of
needed is, 
Answer:
I think it would be 9 moles.
They have used added new elements to the table .
<u>Explanation:</u>
As new elements are discovered chemists add them to the period table leading to the periodic table undergoing continuous modifications. When the first periodic table in the world was formed, very few elements were known to humankind. Earlier periodic tables thus contain lesser number of elements than the modern ones.
Mendeleev's periodic table contained 63 elements arranged in the increasing order of their atomic masses. Modern periodic tables have far more number then the older ones like that of Mendeleev's and the elements are arranged in the order of their atomic numbers.
F - Fluorine
Explanation:
Fluorine is the atom that is most able to attract electrons to itself among the choices. The ability of an atom to attract electron to itself is called electronegativity.
- Electronegativity is a measure of the relative tendency with which atoms of an element attracts valence electrons in a chemical bond.
- Fluorine is the most electronegative element on the periodic table.
- According to Pauling's table on electronegativities of elements, it has a value of 4.0.
- This is the highest on the periodic table of elements.
Learn more:
Electronegativity brainly.com/question/7007192
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