Question

What are the units for molarity? Rearrange the molarity equation to solve for volume

Answer 1

Molarity = moles/liter

molarity = moles / litres
Multiply both sides by litres to remove the division:
molarity X litres = moles
You want answer in litres, so divide each side by molarity:
litres = moles / molarity.

molarity = moles / liters
to start off, you must learn what it means.
lets take an example.
you have 10 moles of salt [ in other words sodium chloride]. you take a 1 liter bottle, dump the salt in, and fill the bottle to the brim with water, and shake well. you now have 1 liter of solution, that is to say, salt and water, with a molarity of 10 moles / liter,
now how did i come up with this equation you ask?
well, its like this. the ' / liter' part of the equation basically means per liter. this means that 10 moles / liter means 10 moles per liter [of solution]. some people confuse this as 10 moles per liter of water - DONT DO THAT. the molarity is 10 moles per liter of solution, ie if you take 1 liter of the solution, you will find 10 moles of the dissolved thing inside it. this is molarity basically - how many moles substance there are in 1 liter of that solution. eg. 2 liters of 2 mole / liter CuSO4 (aq) contains 4 moles of CuSO4, as you have 2 liters of solution, each with 2 moles of CuSO4 in it.

ok, now that thats over, lets move on to proving the thing.
why can molarity = moles/liters be arranged to liters = moles/molarity
well this is just basic math. what the formula means is:

molarity = moles