大学化学英文版.pptVIP

Chapter 2 Solution Equilibrium 溶液平衡 solution (soln) 溶液 solute 溶质, 溶解物 solvent 溶剂 Ways to express Concentration 浓度 Qualitative 定性的 concentrated 浓的 relatively large amount of solute dilute 稀释,冲淡 relatively small amount solute Quantitative 定量的 Ways to express Concentration 浓度 Quantitative 定量的 Mass percentage: ratio of solute mass to total mass, times 100. parts per million 百万分之 (ppm) Mole fraction 摩尔分数 (X) no units 1 mole CH3OH + 9 moles H2O XCH3OH = 0.10 XH2O = 0.90 ? ? molality 质量摩尔浓度 (m)：does not vary with temp, since mass is not temperature dependent. molarity 摩尔浓度 (M)：can vary slightly with temp because the volume of a soln can vary slightly. molarity (M), M = mol/L molality (m), m = mol/kg 0.15 M = 0.15 mol/L 0.23 m = 0.23 mol/kg Homework p 8 4, 5, 6 Do your own Due at the beginning of class Next time 2.2 – 2.3 Bring calculator to class Name in Chinese Name in pinyin student # Major, Class # don’t need to write question 文婧 Wén Jìng 3014XXXXX EE1 电工电子 = electrical engineering = EE 机械工程 = mechanical engineering = ME 工程科学 = engineering science = ES * 2.5 million * * * * * chemistry is experimental science with things that can be measured – units Appendix 1, base SI units Table 1, prefixes Table 2 * * * counting exact even most carefully taken measurement always inexact, has error, uncertainty PA2 Tables 5 and 6 * 0 1000 600 700 800 690 700 710 699 700 701 * the logarithm of a number is the exponent to which another fixed value, the base, must be raised to produce that number. * * Ca Al C Na O Fe Zn F N Ni S Cl Cu K H P Co B Ne Au Pb Br Ar Ni I Ti * * Two kinds ionic and binary Ionic = cation + anion 1 g/100 g = 1% ppm = mg/L, very dilute * All add to 1 * Symbol and unit * SF Rules: 1. (x and ÷) answer has the same number of SF as the measured number with the fewest SF. (1.35 cm)3 = 2.460375 cm3 = density 密度 (g/cm3) 25 cm3 weighs 25.624 g density = 25.624 g/25 cm3 = 1.02496 g/cm3 = 2. (+,