Question

What is the ph of a 2.00 m hno2 solution if ka=5.00 e-6?

Answer 1

Answer: -

2.5

Explanation: -

Initial [HNO₂] = 2.00 M

ka = 5.00 x 10 ⁻⁶

ICE table for HNO₂ =

[$\left[\begin{array}{cccc}concentrations&HNO2&H+&NO2\\Initial&2.00&0&0\\Change&-x&+x&+x\\Equilibrium&2.00-x&x&x\end{array}\right]$

Ka = $\frac{x2}{2.00-x}$

5.00 x 10-6 = $\frac{x2}{2.00-x}$

x = 0.0032 M

pH = - log [H⁺]

= - log 0.0032

= 2.5