Question

HELP!! I keep getting these two questions wrong.

THANK YOU to whoever can help me with this.

If I dissolve KOH in solution to a concentration of 3.4 x 10^-4, what is [OH-] in solution?"

		3.4 x 10-4
		2.94 x 10-11
		Can t be determined without the pKa
		2.94 x 10-10
		3.47

If [H+] in aqueous solution is 6.50 x 10^-6, what is [OH-]?"

		1.67 x 10-4
		1.67 x 10-9
		4.22
		1.67 x 10-10
		6.50 x 10-6

Answer 1

1) KOH is a strong electrolyte thus dissociate completely and give K+ and OH-. Thus, concentration of OH- = concentration of KOH.

Concentration of OH- = 3.4×10^-4

2) [OH-] = 10^-14/[H+] = 10^-14/6.50×10^-6

= 1.67×10^-9