Answer is: C₃H₃N₃O₃.
Chemical reaction: CₓHₓNₓOₓ + O₂ → aCO₂ + x/2H₂ + x/2N₂.
m(CₐHₓNₓ) = 5,214 g.
m(CO₂) = 5,34 g.
m(H₂) = 1,09 g.
m(N₂) = 1,70 g.
n(CO₂) = n(C) =  5,34 g ÷ 44 g/mol = 0,121 mol.
n(H₂O) = 1,09 g ÷18 g/mol = 0,06 mol.
n(H) = 2 · 0,0605 mol = 0,121 mol.
n(N₂) = 1,7 g ÷ 28 g/mol = 0,0607 mol.
n(N) = 0,0607 mol · 2 = 0,121 mol.
n(C) : n(H) : n(N) = 0,121 mol : 0,121 mol : 0,121 mol /: 0,121
n(C) : n(H) : n(N) = 1 : 1 : 1.
M(CHN) = 27 g/mol.
m(O₂) = 8,13 g - 5,214 g = 2,914 g.
n(O₂) = 2,914 g ÷ 32 g/mol = 0,09 mol.
n(CₓHₓNₓOₓ) = 5,214 g ÷ 129,1 g/mol = 0,0404 mol.
n(CₓHₓNₓOₓ) : n(CO₂) = 1 : 3.
        
                    
             
        
        
        
Centimeters are units of length.
        
             
        
        
        
Hello!
The basic equations to solve this is
pH = -log[H+]
pOH = -log[OH-]
pH + pOH = 14
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Find pHpH = -log(1 * 10^-1)
pH = 1
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Find pOH1 + pOH = 14
pOH = 13
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Find OH-[OH-] = 10^(-pOH)
[OH-] = 1 * 10^-13mo/L
The answer is 
![[OH-] = 1 * 10^{-13} mol/L](https://tex.z-dn.net/?f=%5BOH-%5D%20%3D%201%20%2A%2010%5E%7B-13%7D%20mol%2FL)
Hope this helps!