What volume of 1.25m hcl would be required to prepare 180 ml of a 0.500m hcl solution? a. 2.2 x 103 ml b. 450 ml c. 72 ml d. 0.014 ml

To solve this we use the dilution equation used in chemistry, 

M1 V1 = M2 V2

where M1 is the concentration of the stock solution, V1 is the volume of the stock solution, M2 is the concentration of the new solution and V2 is its volume.

M1 V1 = M2 V2

1.25 M x V1 = 0.500 M x 180 mL

V1 =72 mL of the concentrated solution

Therefore, the correct answer would be option C.

number of molecules / avogadro's number * molecule molecular = mass

explanation:

we define a gram-molecular weight as the mass of one mole of any element or compound. a mole contains avogadro's number of units (molecules) –  

6.022

x

10

23

. so, dividing the number of molecules by avogadro's number gives us the number of moles. multiplying that by the molecular weight gives us the mass. from the periodic table we find the gram-molecular weight of u to be238 and of f to be19. so,  

u

f

6

will have a gram-molecular weight of 352g.