Question

2 points

2.7 x 10-2 grams of Pb(C2H302)4 are dissolved to make 3.5 mL of
solution. What is the molarity?
Your Answer

Answer 1

The molarity is 0.0174
`(moles)/(liter)`

Step-by-step explanation:

Molarity (M) or Molar Concentration is the number of moles of solute that are dissolved in a certain volume.

The molarity of a solution is calculated by dividing the moles of the solute by the volume of the solution.

`Molarity=(number of moles of solute)/(volume of solution)`

Molarity is expressed in units
`(moles)/(liter)`.

In this case, being the molar mass of compound Pb(C₂H₃O₂)₄ equal to 443.38 g / mol, then the following rule of three can be applied: if 443.38 grams are contained in 1 mol, 2.7*10⁻² grams in how many moles they are present?

`amount of moles=(2.7*10^(-2) grams*1 mol)/(443.38 grams)`

amount of moles= 6.09*10⁻⁵ moles

Being 1,000 mL= 1 L, then 3.5 mL= 3.5*10⁻³ L

So:

`Molarity=(6.09*10^(-5) moles)/(3.5*10^(-3) L)`

Solving:

Molarity=0.0174
`(moles)/(liter)`

The molarity is 0.0174
`(moles)/(liter)`