Waiting for answer This question has not been answered yet. You can hire a professional tutor to get the answer.

QUESTION

# Nitric acid is usually purchased in concentrated form with a 70.3% HNO3 concentration by mass and a density of 1.41 g/mL.How much of the concentrated stock solution in milliliters should you use to make 1.5L of 0.500M HNO3?

"47.8 mL"

A solution's is defined as the mass of the divided by the total mass of the solution and multiplied by 100.

Nitric acid's concentration by mass is given to be 70.3%; this means that for every "100 g" of solution we get "70.3 g" of "HNO"_3.

Let's assume we have a "1-L" bottle of stock "HNO"_3 solution (we could assume any volume, the answer must always be the same - in this case, 1L makes the calculations easier).

Knowing that the solution's is "1.41 g/mL", which is equal to

1.41"g"/color(red)(cancel(color(black)("mL"))) * (1000 color(red)(cancel(color(black)("mL"))))/"1 L" = "1410 g/L"

we can determine the stock solution's mass

"density" = "mass"/"volume"

so you get

"mass" = "density" * "volume"

m_"sol" = 1410"g"/color(red)(cancel(color(black)("L"))) * 1color(red)(cancel(color(black)("L"))) = "1410 g".

Out of this quantity, 70.3% represents HNO_3, so nitric acid's mass will be

1410 color(red)(cancel(color(black)("g solution"))) * ("70.3 g HNO"""_3)/(100color(red)(cancel(color(black)("g solution")))) = "991.2 g HNO"""_3

Knowing that nitric acid's molar mass is "63 g/mol", we determine the number of moles to be

991.2 color(red)(cancel(color(black)("g"))) * "1 mole"/(63 color(red)(cancel(color(black)("g")))) = "15.7 moles"

Thus, its is

C = n/V = "15.7 moles"/"1 L" = "15.7 M"

We can now apply calculations to determine what the requested volume will be

C_1V_1 = C_2V_2

V_1 = C_2/C_1 * V_2 = (0.5 color(red)(cancel(color(black)("M"))))/(15.7color(red)(cancel(color(black)("M")))) * 1.5 * 10^3"mL" = color(green)("47.8 mL").

I'll leave the answer rounded to three .