# chemistry

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A flask has a mass of 78.23 g when empty and 593.63 g when filled with water. When the same flask is filled with concentrated sulfuric acid, H2SO4, its mass is 1026.57 g. What is the density of concentrated sulfuric acid? (Assume water has a density of 1.00 g/cm3 at the temperature of the measurement.) Enter NUMBERS ONLY in your answer using units of g cm-3. Please make sure you round to the appropriate number of significant figures.

This is what i did
i set the density of water .996g/cm^3 = 593.63g-78.23g/V

Solved for Volume of water and got 517.469

then to find density of sulfer i divided 1026.57/517.469

and got D= 1.983 g/cm3

Very confused though due to significant figures and roundings, can some one check my answer and correct me if i am wrong?.

• chemistry -

This is what i did
i set the density of water .996g/cm^3 = 593.63g-78.23g/V
First, i is I. The original problem lists the density of water as 1.00 g/mL; therefore, you need to correct volume using the proper density value.

Solved for Volume of water and got 517.469
I think the value is closer to 515 something.

then to find density of sulfer i divided 1026.57/517.469
Isn't the mass of H2SO4 1026.57-78.23 = ??

and got D= 1.983 g/cm3
You have 5 s.f. in the water calcn and 3 for the density; therefore, the volume is known to 3 s.f. You can't have more than 3 s.f. in the final answer.