Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Stoichiometry wikipedia , lookup
Safety data sheet wikipedia , lookup
Dimensional analysis wikipedia , lookup
Periodic table wikipedia , lookup
Chemistry: A Volatile History wikipedia , lookup
History of molecular theory wikipedia , lookup
History of chemistry wikipedia , lookup
Atomic theory wikipedia , lookup
IUPAC nomenclature of inorganic chemistry 2005 wikipedia , lookup
Chapter 1 Matter and Measurement Dr. S. M. Condren Chemistry • What is it? • Why do we study it? Dr. S. M. Condren Development of Periodic Table Dmitri Mendeleev - Russian 1869 - Periodic Law - allowed him to predict properties of unknown elements - the elements are arranged according to increasing atomic weights Dr. S. M. Condren Periodic Table of the Periodic Table of the Elements Elements IA 1 1 2 3 4 5 6 7 II A III B IV B VB VI B VII B VIII B IB II B III A IV A VA VI A VII A 1 VIII A 2 H H He 1.008 1.008 3 4 5 6 7 8 9 4.0026 10 Li Be B C N O F Ne 6.939 9.0122 10.811 12.011 14.007 15.999 18.998 20.183 11 12 13 14 15 16 17 18 Na Mg Al Si P S Cl Ar 22.99 24.312 26.982 28.086 30.974 32.064 35.453 39.948 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr 39.102 40.08 44.956 47.89 50.942 51.996 54.938 55.847 58.932 58.71 63.54 65.37 69.72 72.59 74.922 78.96 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 79.909 53 83.8 54 Rb Sr Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I Xe 85.468 87.62 88.906 91.224 92.906 95.94 * 98 101.07 102.91 106.42 107.9 112.41 114.82 118.71 121.75 127.61 126.9 131.29 55 56 57 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 Cs Ba **La Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po At Rn 132.91 137.33 138.91 178.49 180.95 183.85 186.21 190.2 192.22 195.08 196.97 200.29 204.38 207.2 208.98 * 209 * 210 * 222 87 88 89 104 105 106 107 108 109 110 111 112 113 114 115 116 Rf Ha Sg Ns Hs Mt * 261 * 262 * 263 * 262 * 265 * 268 Fr * 223 Ra ***Ac 226.03 227.03 58 * Designates that **Lanthanum all isotopes are Series radioactive *** Actinium Series 59 60 61 62 Uun Uuu Uub * 269 * 272 63 64 * 277 65 Uut 118 Uuq Uup Uuh Uuo *284 *285 *288 *292 Based on symbols used by ACS 66 67 68 69 S.M.Condren 2006 *294 70 71 Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu 140.12 140.91 144.24 * 145 150.36 151.96 157.25 158.93 162.51 164.93 167.26 168.93 173.04 174.97 90 91 92 93 94 95 96 97 98 99 100 101 102 103 Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No Lr 232.04 231.04 238.03 237.05 * 244 * 243 * 247 * 247 * 251 * 252 * 257 * 258 * 259 * 260 Dr. S. M. Condren Dr. S. M. Condren http://mrsec.wisc.edu/Edetc/LEGO/LEGO PT final.html Dr. S. M. Condren Glenn T. Seaborg Winner of the 1951 Nobel Prize in Chemistry Dr. S. M. Condren Physical States • solid – fixed volume and shape • liquid – fixed volume – shape of container, horizontal top surface • gas – takes shape and volume of container • liquid crystal – some characteristics of solid and some of liquid states Dr. S. M. Condren Liquid Crystals Dr. S. M. Condren Amorphous Metal • Atoms in the steel move past each other in the bouncing of the bearing, absorbing some of the energy of the bearing • Amorphous metal is so tightly packed that this does not occur because the atoms of different sizes and randomly pack http://mrsec.wisc.edu/Edetc/SlideShow/slides/amorphous/glass.html Dr. S. M. Condren Properties of Matter Extensive Property • depends on specific sample under investigation • examples: – mass and volume Intensive Property • identical in all samples of the substance • examples: – color, density, melting point, etc. Dr. S. M. Condren Density • Mass per unit of volume d = m/V • Mass equals volume times density m = d*V • Volume equals mass divided by density V = m/d Dr. S. M. Condren Physical Property • one that can be observed without changing the substances present in the sample • changes in physical properties of substances Dr. S. M. Condren Chemical Property • the tendency to react and form new substances Dr. S. M. Condren Chemical Reaction • reactants undergo chemical change to produce products sucrose ---> carbon + water reactant products Dr. S. M. Condren Chemical Reaction Reactions are indicated by: • evolution of a gas • change of color • formation of a precipitate Dr. S. M. Condren Pure Substances Elements Compounds Dr. S. M. Condren Atoms-Molecules-Ions • Atoms – smallest subdivision of an element that retains all of the properties of the element • Molecules – two or more atoms linked (bonded) together • Ions – charged atoms or groups of atoms Dr. S. M. Condren Mixtures Heterogeneous • uneven texture Homogeneous (Solution) • sample uniform throughout Dr. S. M. Condren Matter • What is matter? Anything that has mass and occupies space Dr. S. M. Condren Separation of Matter Dr. S. M. Condren Fractional Distillation Dr. S. M. Condren Soxhlet Extractor Dr. S. M. Condren Important Metric Unit Prefixes deci -- 1/10* centi -- 1/100* milli -- 1/1000* nano -- 1/1,000,000,000 kilo -- 1000* Dr. S. M. Condren Significant Figures Rules for determining which digits are significant: • All non-zero numbers are significant • Zeros between non-zero numbers are significant • Zeros to the right of the non-zero number and to the right of the decimal point are significant • Zeros before non-zero numbers are not significant Dr. S. M. Condren Significant Figures Examples: Regular Lab Balance • 1,000 g + 0.1 g 1.0000 x 103 g 5 sig. fig. • 400 g + 0.01 g 4.0000 x 102 g 5 sig. fig. • 100 + 0.001 g 1.00000 x 102 g 6 sig.fig. Dr. S. M. Condren Rules for Mathematics Multiplication and Division For multiplication and division, the number of significant figures used in the answer is the number in the value with the fewest significant figures. (2075)*(14) ---------------- = 2.0 x 102 (144) 4 sig. fig.; 2 sig.fig.; 3 sig. fig. => 2 sig. fig. Dr. S. M. Condren Rules for Mathematics Addition and Subtraction For addition and subtraction, the number of significant figures used in the answer is determined by the piece of data with the fewest number decimal places. 4.371 302.5 -------306.8 Dr. S. M. Condren Rules for Mathematics Addition and Subtraction For addition and subtraction, the number of significant figures used in the answer is determined by the piece of data with the fewest number decimal places. 4.371 302.5 -------306.8 Dr. S. M. Condren Rules for Mathematics Addition and Subtraction For addition and subtraction, the number of significant figures used in the answer is determined by the piece of data with the fewest number decimal places. 4.371 (I truncate extra data) 302.5 -------306.8 Dr. S. M. Condren Exact Numbers • conversion factors • should never limit the number of significant figures reported in answer 12 inches = 1 foot Dr. S. M. Condren Round Off • Chemistry is an inexact science • all physical measurements have some error • thus, there is some inexactness in the last digit of any number • use what ever round-off procedure you choose • reasonably close answers accepted Dr. S. M. Condren Heat vs. Temperature • heat – a form of energy • temperature – one way of measuring heat – determines the direction of flow of heat Dr. S. M. Condren Comparison of Temperature Scales Fahrenheit Celcius 98.6 37.0 comfort temp. 68.0 20.0 bp water 212 100 mp 32 0 bp-mp 180 100 body temp. Dr. S. M. Condren Temperature Relationships oC = 100/180 * (oF - 32) oF = (180/100)*oC + 32 K = oC + 273.15 - 40o F = - 40o C Dr. S. M. Condren If the temperature of the room goes from 20 degrees C to 40 degrees C, the ambient thermal energy – doubles – is halved – increases by less than 10% Dr. S. M. Condren Problem Solving by Dimensional Analysis • state question in mathematical form • set equal to piece of data specific to the problem • use conversion factors to convert units of data specific to problem to units sought in answer Dr. S. M. Condren Example How many kilometers are there in 0.200 miles? Dr. S. M. Condren Example How many kilometers are there in 0.200 miles? state question in mathematical form #km Dr. S. M. Condren Example How many kilometers are there in 0.200 miles? set equal to piece of data specific to the problem #km = 0.200 miles Dr. S. M. Condren Example How many kilometers are there in 0.200 miles? use conversion factors to convert units of data specific to problem to units sought in answer #km = (0.200 miles) * (5280 ft/mile) Dr. S. M. Condren Example How many kilometers are there in 0.200 miles? cancel units #km = (0.200 miles) * (5280 ft/mile) Dr. S. M. Condren Example How many kilometers are there in 0.200 miles? add another conversion factor #km = (0.200)*(5280 ft) *(12 in/ft) Dr. S. M. Condren Example How many kilometers are there in 0.200 miles? cancel units #km = (0.200)*(5280 ft) *(12 in/ft) Dr. S. M. Condren Example How many kilometers are there in 0.200 miles? #km = (0.200)*(5280)*(12 in) Dr. S. M. Condren Example How many kilometers are there in 0.200 miles? add still another conversion factor #km = (0.200)*(5280)*(12 in) *(2.54 cm/in) Dr. S. M. Condren Example How many kilometers are there in 0.200 miles? cancel units #km = (0.200)*(5280)*(12 in) *(2.54 cm/in) Dr. S. M. Condren Example How many kilometers are there in 0.200 miles? #km = (0.200)*(5280)*(12)*(2.54 cm) Dr. S. M. Condren Example How many kilometers are there in 0.200 miles? add still another conversion factor #km = (0.200)*(5280)*(12)*(2.54 cm) *(1 m/100 cm) Dr. S. M. Condren Example How many kilometers are there in 0.200 miles? cancel units #km = (0.200)*(5280)*(12)*(2.54 cm) *(1 m/100 cm) Dr. S. M. Condren Example How many kilometers are there in 0.200 miles? #km = (0.200)*(5280)*(12)*(2.54) *(1 m/100) Dr. S. M. Condren Example How many kilometers are there in 0.200 miles? add still another conversion factor #km = (0.200)*(5280)*(12)*(2.54) *(1 m/100)*(1 km/1000 m) Dr. S. M. Condren Example How many kilometers are there in 0.200 miles? cancel units #km = (0.200)*(5280)*(12)*(2.54) *(1 m/100)*(1 km/1000 m) Dr. S. M. Condren Example How many kilometers are there in 0.200 miles? #km = (0.200)*(5280)*(12)*(2.54) *(1/100)*(1 km/1000) Dr. S. M. Condren Example How many kilometers are there in 0.200 miles? solve mathematics #km = (0.200)*(5280)*(12)*(2.54) *(1/100)*(1 km/1000) = 0.322 km 3 sig. fig. Dr. S. M. Condren Example How many kilometers are there in 0.200 miles? solve mathematics #km = (0.200)*(5280)*(12)*(2.54) *(1/100)*(1 km/1000) = 0.322 km 3 sig. fig. exact numbers Dr. S. M. Condren