# What volume of this solution is required to make 1.25 L

#### fghtffyrdmns

1. The problem statement, all variables and given/known data

An aqueous stock solution is 85.0% H2SO4 by mass and its density is 1.83 g/mL. What volume of this solution is required to make 1.25 L of 2.75 mol/L H2SO4(aq)? Give your answer in millilitres, accurate to three significant figures.

2. Relevant equations

$$c1v1=c2v2$$

3. The attempt at a solution

What I did was multiply 0.85 by the density, then to convert to liters, multiplied by 1000. To get the concentration, I just divided by the molar mass of H2SO4 (98.086).

Then I could solve for the volume by using the equation.

#### Borek

Mentor
Re: acid-base

Sounds reasonable.

Where is the base?

#### fghtffyrdmns

Re: acid-base

Sounds reasonable.

Where is the base?
That's what's confusing me. If I do this, I get the wrong answer.

#### Borek

Mentor
Re: acid-base

Show numbers, hard to tell what you are doing not seeing details.

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#### fghtffyrdmns

Re: acid-base

$$(0.85)(1.83 g/mL)(1000 mL/L)(1 mol/98.086 g)$$

This gives you the concentration

Then you can simply find the volume with c1v1=c2v2.

#### Borek

Mentor
Re: acid-base

That should give you correct molarity of the solution.

You have shown only part of the calculations, so no way anyone can tell you what and where went wrong. If you expect reasonable help, you have to give reasonable amount of information.

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#### fghtffyrdmns

Re: acid-base

$$v1 = c2v2/c1 v1 = (1.25 L)(2.75 mol/L)/(15.8585 mol/L) = 0.217 L.$$

#### Borek

Mentor
Re: acid-base

Looks OK to me. The only problem is that density of 85% sulfuric acid is not 1.83 g/mL, but if it was given to you you should use it.

You have earlier wrote that you are getting wrong answer, but I have no idea why do you think so - so I can't help further. Really, if you want to be helped, you need to be more elaborate.

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