Given that pKa = 3.74 at 25 °C for HCOOH, what is the pH of 0.113...

Question

Question

Given that pK_a = 3.74 at 25 °C for HCOOH, what is the pH of 0.113 mol L⁻¹ HCOONa(aq) at 25 °C? What is the equilibrium concentration of HCOOH?

Answer 1

Answer #1

An ICE table is made


Initial concentration (M)	0.113	0	0
Change in concentration (M)	-x	+x	+x
Equilibrium concentration (M)	0.113-x	x	x

The base dissociation constant

Since value of Kb is very small, we approximate 0.113-x to 0.113

Hence, the equilibrium concentration of HCOOH is

Answer 2

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