PDF-Empirical Measurements of Disk Failure Rates and Error Rates Jim Gray,

1 System Source Type Part Years Fails Fails Year SCSI 10krpm 858 24 28 controllers 72 2 28 TerraServer SAN Barclay san switch 9 1 111 TerraServer Brick Barclay SATA 7krpm 138 10 72. 1 02 03 04 05 06 07 08 09 1 Measured Value of x Fraction of Total Measurements SD 01 SD 02 SD 03 brPage 5br mean standard deviation histogram Figure 3 Mass of Unknown Sample 102 104 106 108 11 112 114 116 118 12 Mass kg of Measurements brPage 6br Molecular Formulas. Let’s use those mole conversions!. Empirical formula . tells you the lowest ratio of atoms within a molecule. Molecular formula . tells you the actual ratio of atoms within a molecule. You should know this for the quiz!. Empirical and Molecular Formulae. Empirical Formula. If needed, change % to g.. Do . a molar conversion to change from . g. mol. Divide each of these numbers by the smallest number. Antonio A. F. Loureiro. Universidade Federal de Minas Gerais, . Brazil. loureiro@dcc.ufmg.br. IEEE . LatinCom. 2011, . Belém, . Oct. 26, 2011. Looking into the past. What happened to Jim Gray?. On Sunday, Jan 28, 2007, during a short solo sailing trip to the . Objectives. To learn how to work out the percentage composition by weight of a compound. To use percentage composition to work out empirical formulae. Percentage compositions. This means what percentage of each element is present in a compound, and therefore tells you what masses of each element are present in any given mass of a compound. . How can conjectural variation models help?. Alan Crawford and . Benoît. Durand. OFT Seminar. The questions. Can we use conjectural variation models to . measure empirically market power?. identify the source of market power? Can we use conjectural variation models to tell whether market power is the result of product differentiation or collusion? . Chemistry GT 3/20/15. Drill. Calculate the percent composition of Na. 2. SO. 4. .. HW: Molecular Formula WS (pg. 4). MM. =142.05 . g. /mol. 32.37% Na, 22.58% S, 45.05% O. Chem. Joke of the Day. The photon checked into a hotel. What did it say when the bellhop asked for its bag?. Molecular Formulas. Let’s use those mole conversions!. Empirical formula . tells you the lowest ratio of atoms within a molecule. Molecular formula . tells you the actual ratio of atoms within a molecule. Precision. Accuracy. Error Types. Significant Digits. Error Propagation. Error in Measurement.  . "Accuracy" means truth.. "Precision" means detail..  . Accuracy. Accurate: measured value very close to actual value.. Shyam . S. under. JAPP Conference on Accounting and Risk Management. LSE, IE Business School and Univ. of Maryland. College Park, Maryland. May 29, 2014. “It is a veritable Proteus that changes its form every instant.”. The Mole. Chemist’s counting number. amount. of a substance . 1 mole is equal to 6.022 x 10. 23. atoms or particles or molecules (Avogadro’s number). There are always 6.022 x 10. 23 . particles in . Percent Composition. Percent . Composition – . the . percentage . by mass of . each . element in a . compound (*note: not the ratio of elements in the compound). Law of Definite Proportions . – compounds always contain the same proportions of elements by mass.. Due at end of Period. The compound . benzamide. has the following percent composition. What is the empirical formula? . C . = 69.40 % H= 5.825 % O = 13.21 % N= 11.57 % . 2. A . component of protein called serine has an approximate . Determining Molecular Formulas. Calculate the molecular formula of a compound whose molar mass is 60.0 g/mol and has an empirical formula of CH4N.. What you need:. Empirical Formula. Molar Mass. Calculate the molar mass of the empirical formula.