1 / 12

Empirical Formulas

Empirical Formulas. Empirical formula – lowest whole-number ratio of the elements in a compound (divide by – Greatest Common Factor) What is the empirical formula of C 2 N 2 H 8 CNH 4. Empirical Formula Calculations 1.) Change the given information to moles for each element.

lacey
Download Presentation

Empirical Formulas

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Empirical Formulas

  2. Empirical formula – • lowest whole-number ratio of the elements in a compound • (divide by – Greatest Common Factor) • What is the empirical formula of C2N2H8 • CNH4

  3. Empirical Formula Calculations • 1.) Change the given information to moles for each element. • 2.) Divide each mole answer by the smallest number of moles. • 3.) If the answers from step 2 are not whole numbers then divide by the smallest decimal part. • 4.) Write the formula with the mole ratio as subscripts.

  4. EX 1 Find the empirical formula. • A compound contains 9.31g of Ag and 0.69g of O.

  5. Ag2O

  6. EX 2 A compound contains 25.9% N and 74.1% O. • Find the empirical formula.

  7. Nitrogen = 1 ÷ 0.5 = 2 • Oxygen = 2.5 ÷ 0.5 = 5 N2O5

  8. MOLECULAR FORMULAS

  9. Molecular formula – empirical formula or its multiple • Several compounds can have the same empirical formula but different molecular formulas. • What is the empirical formula of C2N2H8? • CNH4 • What is the molecular formula of CNH4? • C2N2H8

  10. Convert molecular  empirical • Divide subscripts by greatest common factor • Convert empirical  molecular • multiply subscripts by …

  11. EX 1 • The empirical formula is CH4N and the molar mass is 60.0 g. Find the molecular formula. • C 1 X 12.0 = 12.0g • 4H 4 X 1.0 = 4.0g • N 1 X 14.0 = 14.0g • 30.0g C2H8N2

  12. EX 2 • Find the molecular formula of C4H6O if the molar mass is 280.0g. • 4C 1 X 12.0 = 48.0g • 6H 4 X 1.0 = 6.0g • O 1 X 14.0 = 16.0g • 70.0g C16H24O4

More Related