You’ve just started a new job in the laboratory of the Food and Drug Administration. Your supervisor asks you to prepare a 1.50-M solution of aqueous potassium permanganate, KMnO4. What mass of KMnO4 will you need to prepare 500 mL of this solution?

 118.5 grams

Explanation:

Molarity is defined as the number of moles of solute dissolved per liter of the solution.

where,

n= moles of solute

= volume of solution in ml = 500 ml

moles = 0.75

moles of solute =

0.75 =

mass of = 118.5 grams

Thus mass of needed to prepare 500 mL of this solution iis 118.5 grams

c. because step up transformer steps up the input voltage i.e increases the input voltage  

the number of turns are greater on the secondary side of step up transformer  

transformer does not handle dc current

the volume increases