By what I have learned I don't think that is chemical but if I had to guess I would say the chemical treatment is they are exposed to air
Answer:
Molecular formula = P₄O₁₀
Explanation:
Given data:
Empirical formula of compound = P₂O₅
Molar mass of compound = 426 g/mol
Molecular formula = ?
Solution:
Molecular formula:
Molecular formula = n (empirical formula)
n = molar mass of compound / empirical formula mass
Empirical formula mass= P₂O₅ = 283.89 g/mol
n = 426 g/mol / 283.89 g/mol
n = 2
Molecular formula = n (empirical formula)
Molecular formula = 2 (P₂O₅ )
Molecular formula = P₄O₁₀
500 water molecules and the remaining 500 O2 molecules. Remember the ratio of H to O in H2O.
Answer:
a) 129.14 g/mol
b) 8.87
Explanation:
Given that:
mass of the ionic compound [NaA] = 18.08 g
Volume of water = 116.0 mL = 0.116 L
Let the mole of the acid HCl = 0.140 M
Volume of the acid = 500.0 mL = 0.500 L
pH = 4.63
= 1.00 L
Equation for the reaction can be represented as:

From above; 1 mole of an ionic compound reacts with 1 mole of an acid to reach equivalence point = 0.140 M × 1.00 L
= 0.140 mol
Thus, 0.140 mol of HCl neutralize 0.140 mol of ionic compound at equilibrium
Thus, the molar mass of the sample = 
= 129.14 g/mol
b) since pH = pKa
Then pKa of HA = 4.63
Ka = ![10^{-4.63]](https://tex.z-dn.net/?f=10%5E%7B-4.63%5D)
= 
![[A^-]equ = \frac{0.140M*1.00L}{1.00L+0.116L}](https://tex.z-dn.net/?f=%5BA%5E-%5Dequ%20%3D%20%5Cfrac%7B0.140M%2A1.00L%7D%7B1.00L%2B0.116L%7D)

= 0.1255 M
of HA = 


+
+ 
Initial 0.1255 0 0
Change - x + x + x
Equilibrium 0.1255 - x x x
![K_b = \frac{[HA][OH^-]}{[A^-]}](https://tex.z-dn.net/?f=K_b%20%3D%20%5Cfrac%7B%5BHA%5D%5BOH%5E-%5D%7D%7B%5BA%5E-%5D%7D)
![4.35*10^{-10} = \frac{[x][x]}{[0.1255-x]}](https://tex.z-dn.net/?f=4.35%2A10%5E%7B-10%7D%20%3D%20%5Cfrac%7B%5Bx%5D%5Bx%5D%7D%7B%5B0.1255-x%5D%7D)
As
is very small, (o.1255 - x) = 0.1255

[OH⁻] = 
But pOH = - log [OH⁻]
= - log [
]
= 5.13
pH = 14.00 = 5.13
pH = 8.87
<span>Chemical reactions at the Earth’s surface </span>