Yahoo Answers is shutting down on May 4th, 2021 (Eastern Time) and beginning April 20th, 2021 (Eastern Time) the Yahoo Answers website will be in read-only mode. There will be no changes to other Yahoo properties or services, or your Yahoo account. You can find more information about the Yahoo Answers shutdown and how to download your data on this help page.
Trending News
CHemistry problem need help i do not understand?
Terephthalic acid is an important chemical used in the manufacture of polyesters and plasticizers. It contains only C, H, and O. Combustion of 15.85 mg terephthalic acid produces 33.58 mg CO2 and 5.16 mg H2O. If 0.250 mol of terephthalic acid has a mass of 41.5 g, determine the molecular formula of terephthalic acid.
please explain every step and show work
1 Answer
- Dr.ALv 71 decade agoFavorite Answer
moles CO2 = 0.03358 g/44.009 g/mol=0.0007630
= moles C
mass C = 0.0007630 mol x 12.011 g/mol=0.009165 g
moles H = 2 x 0.00516/18.02 g/mol=0.000573
mass H = 0.000573 x 1.008 g/mol=0.000578 g
mass O = 0.01585 - ( 0.000578 + 0.009165)=0.006107 g
moles O= 0.006107/15.999 =0.0003817
divide by the smallest number
0.0007630/ 0.0003817 = 2 => C
0.000573/ 0.0003817= 1.5 => H
0.0003817/0.0003817 = 1 => O
to grt whole numbers multiply by 2
C4H3O2 ( empirical formula : molar mass =83 g/mol)
molar mass compound = 41.5/0.250 = 166 g/mol
166/83 = 2
multiply by 2 the empirical formula
C8H6O4 = molecular formula
