WA03_CHE-121-mar14 - Thomas Edison State College General...

Info icon This preview shows pages 1–3. Sign up to view the full content.

Thomas Edison State College General Chemistry I with Labs (CHE-121) Section no.: OL009 Semester and year: May 2015 Written Assignment 3: Mass Relationships for Compounds Answer all assigned questions and problems, and show all work. 1. How many atoms are there in 5.10 moles of sulfur (S)? (6 points) (5.10)(6.02 x 10 23 atoms/mol) = 3.07 x 10 24 atoms (Reference: Chang 3.13) 2. How many moles of calcium (Ca) atoms are there in 77.4 g of Ca? (6 points) 77.4g Ca x 1 mole Ca/40.08g Ca = 1.931 mole Ca (Reference: Chang 3.15) 3. What is the mass in grams of 1.00 × 10 12 lead (Pb) atoms? (8 points) (1.00 x 10 12 )(207.2)/6.02 x 10 23 = 3.44 x 10 -10 (Reference: Chang 3.19) 4. Describe how you would determine the isotopic abundance of an element from its mass spectrum. (6 points) Calculate relative atomic mass and that will determine number of isotopes for the element. (Reference: Chang 3.32) 5. Cinnamic alcohol is used mainly in perfumery, particularly in soaps and cosmetics. Its molecular formula is C 9 H 10 O. a. Calculate the percent composition by mass of C, H, and O in cinnamic alcohol. (8 points) 9 x 12g/mole = 108.0g C 1 Copyright © 2014 by Thomas Edison State College. All rights reserved.
Image of page 1

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

10 x 1.01g/mole = 10.1g H
Image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern