Question

‏How many grams of KMnO , are needed to make 500.0 mL of a 0.200 M solution ?

Answer 1

Answer:

See below

Explanation:

Concentration = moles / volume of solution

or

moles = concentration (moles/liter)  X  volume of solution (liter)

Convert your volume to liters  500 mL is 0.500 L

moles = 0.200 moles/liter   x   0.500 liter   (liters cancel each other out)

moles = 0.100 moles

KMnO mass is 110 grams/mole

grams KMnO =  110 grams/mole  x  0.100 moles

                      =  11 grams

Just in case you wrote your question wrong and you meant KMnO₄

KMnO₄ mass is 158 grams/mole

grams KMnO₄ = 158 grams/mole   x   0.100 moles

                        =  15.8