Answer:
[H₃O⁺] = 3.162 × 10⁻⁹ moles / liter
Explanation:
The pH is calculated with the formula:
pH = -lg[H₃O⁺]
From here the concentration of hydronium ion (H₃O⁺) will be:
[H₃O⁺] = 
[H₃O⁺] = 
[H₃O⁺] = 3.162 × 10⁻⁹ moles / liter
Hi!
The Samurai is what I would attribute to the memory of Ancient<span> Japan.</span>
To rank the effective nuclear charge Z* experienced by a valence electrons of a set of atoms that belong to a same period, you only need to apply the rule of trend: it increases as you move from left to right in the period.
So, lets do it for these atoms: P, Al, Si, Cl
The belong to a same period and the order is Al, Si, P, Cl (just see a periodic table). So the rank is Al < Si < P < Cl
Now, lets do it for these atoms:, Be, Ne, O, C
They belong to the second period. The order is Be, C, O, Ne
So, the rank is Be < C < O < Ne.
