Answer:
pH = 2.462.
Explanation:
Hello there!
In this case, according to the reaction between nitrous acid and potassium hydroxide:
It is possible to compute the moles of each reactant given their concentrations and volumes:
Thus, the resulting moles of nitrous acid after the reaction are:
So the resulting concentration considering the final volume (20.00mL+13.27mL) is:
![[HNO_2]=\frac{6.73x10^{-4}mol}{0.01327L+0.02000L} =0.02023M](https://tex.z-dn.net/?f=%5BHNO_2%5D%3D%5Cfrac%7B6.73x10%5E%7B-4%7Dmol%7D%7B0.01327L%2B0.02000L%7D%20%3D0.02023M)
In such a way, we can write the ionization of this weak acid to obtain:
So we can set up its equilibrium expression to obtain x as the concentration of H3O+:
![Ka=\frac{[NO_2^-][H_3O^+]}{[HNO_2]}\\\\7.1x10^{-4}=\frac{x^2}{0.02023M-x}](https://tex.z-dn.net/?f=Ka%3D%5Cfrac%7B%5BNO_2%5E-%5D%5BH_3O%5E%2B%5D%7D%7B%5BHNO_2%5D%7D%5C%5C%5C%5C7.1x10%5E%7B-4%7D%3D%5Cfrac%7Bx%5E2%7D%7B0.02023M-x%7D)
Next, by solving for the two roots of x, we get:
Whereas the correct value is 0.003451 M. Finally, we compute the resulting pH:
Best regards!
Answer:
Correct answer is: "Cold Water"
Explanation:
EDGE 2020
Mouthwash:
solvent - water
solute - alcohols
vinegar:
solvent - water
solute - acetic acid
bleach:
solvent - water
solute - sodium hypochlorite
hope this helps!!
Hey there!
The molar mass of magnesium is 24.305 grams.
The molar mass of an element is the same as the atomic mass of an element, but measured in grams.
It's on the periodic table underneath the element symbol.
Hope this helps!
Answer:
Color Changes. A change in color often indicates a chemical change.
Temperature Changes. Changes in temperature might also indicate a chemical change has occurred.
Precipitates. The formation of a precipitate is a sign that a chemical change has occurred.
Light Emission.
Gas Production.
Explanation:
