Question

2.00 g of NaOH are dissolved in water to make 4.00 L of solution. What is the concentration of hydronium ions, [H3O+], in this solution? How can I work this problem? The book was no help.

Answer 1

Use the idea that NaOH completely dissociates to find the moles of hydroxide ions.

Answer 2

Divide that by the total volume to find molarity.

Answer 3

Find pOH using pOH=-log[OH-}

Answer 4

Find pH using pH+pOH=14

Answer 5

Find concentration of hydronium using pH=-log[H3O+]

Answer 6

So 2.00g of NAOH is equal to how many mol of NaOH? Use the molar mass? I hate stoichiometry.

Answer 7

Yep, molar mass and balanced dissociation reaction.