1 / 15

Comparing Molecules and Compounds: Mass and Formula

This section focuses on comparing the mass of different molecules, such as water and calcium carbonate. It covers essential concepts in chemistry, including atomic mass units (amu), the formula mass of compounds, and how to determine the mass of a molecule using its chemical formula. The chapter discusses the significance of Avogadro’s number and how it relates to the amount of substance in grams. Understanding these concepts allows for accurate calculations and comparisons among various chemical compounds.

jennifer-jenkins
Télécharger la présentation

Comparing Molecules and Compounds: Mass and Formula

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. Chapter 19: Molecules and Compounds Section 19.3 Comparing Molecules

  2. COMPARING DIFFERENT MOLECULES • How does the mass of different molecules compare?

  3. Do you think that a molecule of water has the same mass as a molecule of calcium carbonate?

  4. Recall atomic mass units (amu)… 6CCarbon12.0107 24 • Atoms are assigned a ________________ on carbon as the standard. • Known as atomic mass unit

  5. 19.3 Comparing Molecules

  6. Chemical formula gives 3 pieces of info: • _____ / _______ of atoms. • if ________ ions are present. • allows calculation of mass of 1 molecule of a compound relative to mass of other compounds.

  7. Formula Mass • Formula mass is determined by _____ up the atomic mass unit (amu) of all the atoms in the compound. • The atomic masses are listed on the ________ table.

  8. Example: Figuring Formula Mass • H2O means 2H and 1O • 2 (1.01 amu) =_____ +1 (16.00 amu) = ____ • Formula mass= ____ amu of H2O

  9. An amu is very small, so to be usable in measurements, we equate the _____________ of the formulamass in amu to an equalamount in _____.

  10. Avogadro’s Number • The formula mass in grams of any element or compound contains ____ ______ atoms or molecules. • Known as Avogadro’s # or a “____” of the substance.

  11. So, how do we use this value? • If you measure out 100.09 grams of CaCO3, you have 6.02 x 1023 molecules of CaCO3. • Likewise, 18.02 g of H2O contains 6.02 x 1023 molecules of water.

  12. Example: BaCl2 2H2O • 1 Ba = 1(137.30) = 137.30 • 2 Cl = 2(35.45) = 70.90 • 4 H = 4(1.01) = 4.04 • 2 O = 2(16.00) = 32.00 Formula mass = 244.24 amu

More Related