Lecture1_082608

# Lecture1_082608 - Page 1 of 6 Lecture 1 Importance of Units...

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

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

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Page 1 of 6 Lecture 1 - August 26, 2008 Importance of Units: Numbers without units are like people without names. SI units will be used predominantly: Primary S.I. Units: Quantity Symbol Unit Symbol for Unit Length L meter m Mass m kilogram kg Time t second s Temperature T Kelvin K Electrical Current I Ampere A Secondary S.I. Units: Quantity Symbol Unit Symbol for Unit Volume V = L 3 m 3 Acceleration a = d 2 x/dt 2 m•s-2 Force F = m•a Newton 1 N = 1 kg•m•s-2 Work, Heat, Energy W = F• Δ x Joule 1 J = 1 N•m Power P = W/t Watt 1 W = 1 J•s-1 Pressure, Energy Density p = F/A Pascal 1 Pa = 1 N•m-2 = 1 J•m-3 Electrical Charge Q = I•t Coulomb 1 C = 1 A•s Electric Potential Δ V = E/Q Volt 1 V = 1 J•C-1 Electric Resistance R = Δ V/I Ohm 1 Ω = 1 V•A-1 Electric Capacitance C = Q/ Δ V Farad 1 F = 1 C•V-1 Other commonly used units you need to know are: Length: Angstrom, Å = 10-10 m and Micron, μ = 10-6 m Volume: Liter, L = 10-3 m 3 and Milliliter, mL = 1 cm 3 Force: Dyne, dyn = 10-5 N Pressure: Bar, bar = 10 5 Pa Atmosphere, atm = 101325 Pa Torr, Torr = 133.222 Pa Millimeters of Mercury, mmHg = 1 Torr = 133.222 Pa Energy: Erg, erg = 10-7 J and Calorie, cal = 4.184 J Temperature: Degrees Celsius, °C = K - 273.15 Page 2 of 6 SI Prefixes (Inside front cover of text): Prefix Symbol Multiplier deci d 10-1 centi c 10-2 milli m 10-3 micro μ 10-6 nano n 10-9 pico p 10-12 femto f 10-15 atto a 10-18 deka D 10 kilo k 10 3 mega M 10 6 giga G 10 9 tera T 10 12 Concepts 1) Atomic and Molar Masses in Nuclide Notation: z = atomic number N = number of neutrons Mass #, A = z + N Q A z , examples are different isotopes of carbon and hydrogen C 12 6 , C 13 6 , C 14 6 and H 1 1 , H 2 1 , H 3 1 2) Atomic Mass Units = u = exactly 1/12 the mass of one atom of C 12 6 = 1.66 x 10-27 kg Multiplication by Avogadro's Number (N A = 6.02214 x 10 23 ) gives a molar mass of 10-3 kg 3) Relative Atomic Masses, Ar, are defined as Ar = m/u. 3) Relative Atomic Masses, Ar, are defined as Ar = m/u....
View Full Document

## This note was uploaded on 09/29/2008 for the course CHEM 3615 taught by Professor Aresker during the Fall '07 term at Virginia Tech.

### Page1 / 6

Lecture1_082608 - Page 1 of 6 Lecture 1 Importance of Units...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online