How many grams of potassium hydroxide are needed to prepare 600 ml of a.450 m koh solution?

Remember the formula for molarity:


Where the volume is in liters.

From here, it's a "plug and chug" type of question.

They give you the molarity: 0.45M
They give you the volume: 600mL
Remember that there are 1000mL in every liter, so the converted volume is 0.6L.

Plug in what you have:

To find moles, you need to multiply 0.45 by 0.6, which gives you 0.270 moles.

With moles you can find grams by multiplying 0.270 moles by the molar mass of the compound.

Hope that helps!

Ions gain or lose electrons