{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

u6 - m v MOL p Chemistry Unit 6 The Mathematics of Chemical...

Info icon This preview shows pages 1–9. Sign up to view the full content.

View Full Document Right Arrow Icon
Unit 6: The Mathematics of Chemical Formulas Chemistry Na2CO3 . 10 H2O p v MOL m Cu(OH)2 SO3
Image of page 1

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

View Full Document Right Arrow Icon
# of H2O molecules # of H atoms # of O atoms 1 2 3 100 6.02 x 1023 1 2 4 16.0 g 2 6 3 100 200 2 (6.02 x 1023) 6.02 x 1023 2.0 g 18.0 g molar mass : the mass of one mole of a substance
Image of page 2
Pb O 2 H NO3 ammonium phosphate Pb : 1 (207.2 g) = 207.2 g O : 2 (16.0 g) = 32.0 g 239.3 g H : 1 (1.0 g) = 1.0 g N: 1 (14.0 g) = 14.0 g 63.0 g O: 3 (16.0 g) = 48.0 g ( NH4 )3 PO4 H: 12 (1.0 g) = 12.0 g N: 3 (14.0 g) = 42.0 g 149.0 g P: 1 (31.0 g) = 31.0 g NH41+ PO43 O: 4 (16.0 g) = 64.0 g
Image of page 3

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

View Full Document Right Arrow Icon
percentage composition : the mass % of each element in a compound Find % composition. Pb O 2 ( NH4 )3 PO4 % of element = g element molar mass of compound x 100 207.2 g Pb 239.2 g : = 86.6% Pb 32.0 g O 239.2 g = 13.4% O 31.2 g P 149.0 g = 20.8% P 64.0 g O 149.0 g = 43.0% O 42.0 g N 149.0 g = 28.2% N 12.0 g H 149.0 g = 8.1% H : : : : : (see calcs above)
Image of page 4
zinc acetate Zn2+ CH3COO1– Zn ( CH3COO )2 183.4 g = 3.3% H = 34.9% O = 35.7% Zn = 26.2% C : C: 4 (12.0 g) = 48.0 g Zn : 1 (65.4 g) = 65.4 g H: 6 (1.0 g) = 6.0 g O: 4 (16.0 g) = 64.0 g 183.4 g
Image of page 5

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

View Full Document Right Arrow Icon
“What’s your flavor of ice cream?” Finding an Empirical Formula from Experimental Data 1. Find # of g of each element. 2. Convert each g to mol. 3. Divide each “# of mol” by the smallest “# of mol.” 4. Use ratio to find formula. A compound is 45.5% yttrium and 54.5% chlorine. Find its empirical formula. YCl3 Y g 45.5 Y g 88.9 Y mol 1 Y mol 0.512 = 0.512 ÷ 1 Cl g 54.5 Cl g 35.5 Cl mol 1 Cl mol 1.535 = 0.512 ÷ 3
Image of page 6
A ruthenium/sulfur compound is 67.7% Ru. Find its empirical formula. RuS1.5 Ru2S3 Ru g 67.7 Ru g 101.1 Ru mol 1 Ru mol 0.670 = 0.670 ÷ 1 S g 32.3 S g 32.1 S mol 1 S mol 1.006 = 0.670 ÷ 1.5
Image of page 7

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

View Full Document Right Arrow Icon
A 17.40 g sample of a technetium/oxygen compound contains 11.07 g of Tc. Find the empirical formula.
Image of page 8
Image of page 9
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