Hydroxyl ions are OH⁻ while hydronium ions are H₃O⁺ which is essentially H⁺ ions. The formula for pH is: pH = -log[H⁺]. So, the greater the concentration of H⁺ is, the lower the pH which indicates acidity. On the other hand, the greater the concentration of OH⁻, the greater the pH which indicates basicity. This is also a consequence of the equation: pH + pOH = 14.
A Campfire is an example, the solid wood becomes ash.
Ok first, we have to create a balanced equation for the dissolution of nitrous acid.
HNO2 <-> H(+) + NO2(-)
Next, create an ICE table
HNO2 <--> H+ NO2-
[]i 0.139M 0M 0M
Δ[] -x +x +x
[]f 0.139-x x x
Then, using the concentration equation, you get
4.5x10^-4 = [H+][NO2-]/[HNO2]
4.5x10^-4 = x*x / .139 - x
However, because the Ka value for nitrous acid is lower than 10^-3, we can assume the amount it dissociates is negligable,
assume 0.139-x ≈ 0.139
4.5x10^-4 = x^2/0.139
Then, we solve for x by first multiplying both sides by 0.139 and then taking the square root of both sides.
We get the final concentrations of [H+] and [NO2-] to be x, which equals 0.007M.
Then to find percent dissociation, you do final concentration/initial concentration.
0.007M/0.139M = .0503 or
≈5.03% dissociation.
Answer: Percent composition by element
Element Symbol Mass Percent
Hydrogen H 6.498%
Carbon C 19.357%
Nitrogen N 22.574%
Oxygen O 51.571%
HOPE THIS HELPS
