1 / 31

Chemistry and the Elements

Properties of Matter10. Metals: Found on left side of periodic table.Nonmetals: Found on the right side of periodic table.Semimetals: Form a zigzag line at the boundary between metals and nonmetals. . How were some of the first elements discovered?. Ten elements were discovered before recorded

gaetana
Download Presentation

Chemistry and the Elements

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

    29. What is the mass of a mol of 1H atoms? 1.67x10-24 g/atom x 6.01 x 1023 atoms = 10x10-1g The mass of a mol of hydrogen atoms is 1 g What is the mass of a 35Cl atom? 35Cl = 17p+18n 17(1.67x10-24g) + 18(1.67x10-24g) 35Cl 35(1.67x10-24g) = 58.5 x 10-24g What is the mass of a mol of 35Cl atoms? 35Cl 35(1.67x10-24g) x 6.01x 1023 = 35 What is the mass of a 37Cl atom? 37Cl = 17p+20n 17(1.67x10-24g) + 20(1.67x10-24g) 37Cl 37(1.67x10-24g) = 61.8 x 10-24g What is the mass of a mol of 37Cl atoms? 37Cl 37(1.67x10-24g) x 6.01x 1023 = 37 Previously we defined: Atomic Weight as the sum of the number of protons and neutrons in the nucleus Let us now define the Gram Atomic Weight as the weight in grams of a mol of an element

    30. Since the mass of a neutron and proton are nearly identical and since each element of the perioic table differs only in the number of protons and neutrons in the nucleus, an element with X number of neutrons and Y protons in the nuclues will have an atomic weight of X+Y, and a mol of the element will consist of X+Y grams since: X+Y (1.67x10-24 g x 6.01 x 1023 atoms/mol) = X+Yg Atomic Weight is defined as X+Y Gram Atomic Weight is defined as (X+Y)g.

More Related