Chapter 4 - Chapter 4 Calculation Used in Analytical...

Info icon This preview shows pages 1–7. Sign up to view the full content.

View Full Document Right Arrow Icon
Chapter 4 Calculation Used in Analytical Chemistry Some Important Units of Measurement SI units: Scientists throughout the world have adopted a standardized system of units known as the International System of Units or SI units . The system is based on metric system (such as Mass: kg; Length: m; Time: s; Temperature: K; Amount of substance: mol; Electric current: A etc.). Other units are derived from the base units.
Image of page 1

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

View Full Document Right Arrow Icon
Image of page 2
Prefixes are used with the base units and other derived units to express small or large measured quantities in terms of a few simple digits (such as giga: 10 9 ; mega: 10 6 ; Kilo: 10 3 ; deci: 10 -1 ; centi: 10 -2 : milli: 10 -3 ; micro: 10 -6 ; nano: 10 -9 ; pico: 10 -12 ; femto: 10 -15 ; atto: 10 -18 etc.). The Mole: The mole is the SI unit for the amount of chemical species. The mole is associated with a chemical formula and Avogadro’s number (6.022 x 10 23 ) of particles. The molar mass (M) of a substance is the mass in grams of one mole of the substance. Molar masses are calculated by summing the atomic masses of all the elements appearing in a chemical formula.
Image of page 3

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

View Full Document Right Arrow Icon
Image of page 4
Molar Mass of formaldehyde CH 2 O Molar Mass of glucose C 6 H 12 O 6 M m o l C m o l C H O g m o l C m o l H m o l C H O g m o l H m o l O m o l C H O g m o l O g m o l C H O C H O 2 1 1 2 0 2 1 0 1 1 6 0 3 0 0 2 2 2 2 = × + × + × = . . . . / M m o l C m o l C H O g m o l C m o l H m o l C H O g m o l H m o l O m o l C H O g m o l O g m o l C H O C H O 6 1 2 6 6 1 2 0 1 2 1 0 6 1 6 0 1 8 0 0 6 1 2 6 6 1 2 6 6 1 2 6 6 1 2 6 = × + × + × = . . . . /
Image of page 5

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

View Full Document Right Arrow Icon
Mass and Weight: Mass is an invariant measure of the amount of matter in an object. Weight is the force of attraction between an object and earth. The weight of an object depends on the location because gravitational attraction varies with geographic location. The mass of an object remains constant regardless of locations. A chemical
Image of page 6
Image of page 7
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