You would use a pie chart to best display your results
Cu = 63.546
N= 14.001 g/mol
O= 15.999 g/mol * 3 = 47.997
Copper (II) Nitrate has a MW of 125.544 g/mol
6.25 x 125.544
= 784.65 <--- is your answer, if there were was a multiple choice or not :)
Answer:

Explanation:
Hello,
In this case, in order to compute the grams of sodium chloride starting by the molecules, the first step is to compute the moles contained in the given amount of molecules by using the Avogadro's number:

Then, by using the molar mass of sodium chloride (58.45 g/mol) we can directly compute the grams:

Regards.
Answer:
a. pka = 3,73.
b. pkb = 10,27.
Explanation:
a. Supposing the chemical formula of X-281 is HX, the dissociation in water is:
HX + H₂O ⇄ H₃O⁺ + X⁻
Where ka is defined as:
![ka = \frac{[H_3O^+][X^-]}{[HX]}](https://tex.z-dn.net/?f=ka%20%3D%20%5Cfrac%7B%5BH_3O%5E%2B%5D%5BX%5E-%5D%7D%7B%5BHX%5D%7D)
In equilibrium, molar concentrations are:
[HX] = 0,089M - x
[H₃O⁺] = x
[X⁻] = x
pH is defined as -log[H₃O⁺]], thus, [H₃O⁺] is:
![[H_3O^+]} = 10^{-2,40}](https://tex.z-dn.net/?f=%5BH_3O%5E%2B%5D%7D%20%3D%2010%5E%7B-2%2C40%7D)
[H₃O⁺] = <em>0,004M</em>
Thus:
[X⁻] = 0,004M
And:
[HX] = 0,089M - 0,004M = <em>0,085M</em>
![ka = \frac{[0,004][0,004]}{[0,085]}](https://tex.z-dn.net/?f=ka%20%3D%20%5Cfrac%7B%5B0%2C004%5D%5B0%2C004%5D%7D%7B%5B0%2C085%5D%7D)
ka = 1,88x10⁻⁴
And <em>pka = 3,73</em>
b. As pka + pkb = 14,00
pkb = 14,00 - 3,73
<em>pkb = 10,27</em>
I hope it helps!
There are several ways to express the concentration of solutions. They can be expressed in terms of fraction or percent, in terms of moles or mass for a given mole, mass or volume of solution.
Mass percent is the relationship between the mass of the solute and the mass of the solvent multiplied by 100%. Without multiplying the ratio by 100%, the mass fraction of the solution is obtained.
*Mass percent = <u> </u><u>mass of solute </u> x 100%<u>
</u> mass of solution<u>
</u>