more Chem.
Calculate the amount of solute needed to prepare the following solutions:
a. 50.0mL of a 5.0% (m/v) KCl solution
b. 1250 mL of a 4.0% (m/v) NH4Cl solution

Question

more Chem. 
Calculate the amount of solute needed to prepare the following solutions:
a. 50.0mL of a 5.0% (m/v) KCl solution
b. 1250 mL of a 4.0% (m/v) NH4Cl solution

anonymous · Answer

A. 0.05 = kg KCl / 0.05L


B. 0.04 = kg NH4Cl / 1.25L

anonymous · Answer

ok so (%(m/v))=5.0%
100(m/50.0ml)=5.0%
lets get rid of the % sign by dropping the % sign from the other side
m/50.0ml=5
m=250 and i bet its in grams okf KCl

anonymous · Answer

^i meant the 100 from the other side not the % sign twice ;)