General Chemistry (Chem110) Dr. Rima Alharthy

Transcription

1 General Chemistry (Chem110) Dr. Rima Alharthy Assistant professor in Medicinal and organic synthesis University of Nottingham, UK Building 4 room 204 Office hours (Mondays and Wednesdays 8:00-9:30 a.m.) Chapter 1 (p1-p22)

2 CHEM 110 No. of Units 1 Course No. Course Title Pre-requisites Th. Pr. Credit Chem 110 General Chemistry I Course Objectives: The course aims to introduce students to the basic knowledge and principles of chemistry. Course Description: It provides an introduction to the general principles of chemistry for students planning a professional career in chemistry, a related science, the health professions, or engineering. By the end of this course the student will be able to understand the following: Significant figures, scientific notation and units, stoichiometry, atomic structure & periodic table, chemical bonding, gases, ionic equilibrium, basic principles of organic and basic principles of biochemistry. Main text book: Chemistry, by Chang, 10 th. ed., 2007, McGraw-Hill.

3 Exam schedule (Chapters 1,2,3,4,5,7,8,9,14,15,24,25) 1 st exam : ( Chapters 1-4) = 30 marks 2 nd exam: (Chapters 5,7-9) = 30 marks Final exam: all chapters = 40 marks

4 Chapter 1: Chemistry: The Study of Change Matter Measurements International System of units (SI) Mass and Weight Volume Density Temperature scales

5 Introduction Chemistry is the study of matter and the changes it undergoes Matter is anything that occupies space and has mass Substance is a form of matter that has a definite composition and distinct properties Chemical and Physical properties Physical properties can be measured without changing the composition of substance unlike chemical properties

6 States of matter

7 International System of Units (SI)

8 Scientific notation Power of 10 is any of the integer powers of the number ten; in other words, ten multiplied by itself a certain number of times 100 = 1x = 1x = 1x = 1x = 1x = 1x10-3

9 Example 1.29 Express the following numbers in scientific notation a) b) 356 c) d) 0.096

10 Conversions: note prefixes subtraction subtraction tera T giga G mega M kilo k metre m deci d Centi c milli m micro μ nano n pico p Addition (only if crossing m) Rules Position units on the metric scale Subtract in areas not crossing m Add in areas crossing m From large to smaller unit use + sign From small to larger unit use sign

11 Conversions: note prefixes subtraction subtraction tera T giga G mega M kilo k metre m deci d Centi c milli m micro μ nano n pico p Addition (only if crossing m) A. Convert 7.9x10-2 Gm m? B. Convert 1.4x10-4 cm m? C. Convert 5x10 4 Tm m?

12 Conversions: note prefixes subtraction subtraction tera T giga G mega M kilo k metre m deci d Centi c milli m micro μ nano n pico p Addition (only if crossing m) A. Convert 2x10 3 Gm km? B. Convert 7.5x10-4 nm dm? C. Convert 3x10 4 Tm mm?

13 Examples 1-Express 7.5 ng as Tg A. 7.5 X10-21 Tg B. 75 X10 24 Tg C Tg D. 7.5 X10 21 Tg 2-Which of these quantities represents the largest mass? A mg B kg C g D cg 3-How many micrometers in 6 km? A µm B µm C µm D µm

14 Measurement Mass is a measure of amount of matter in object SI unit of mass is kilogram (kg) 1 kg = 1000 g = 1 x 10 3 g Mass is constant and is independent on location Weight The force that gravity exerts on an object Weight depends on location of object

15 Measurement Volume Volume (V) = Width x Length x Height SI unit of volume is cubic meter (m 3 ) 1 cm 3 = (1 x 10-2 m) 3 = 1 x 10-6 m 3 1 dm 3 = (1 x 10-1 m) 3 = 1 x 10-3 m 3 1 L = 1000 ml = 1000 cm 3 1 L = 1 dm 3 1 ml = 1 cm 3

16 Examples Convert the followings to m 3 A. 2.5x10 4 cm 3 B. 1.20x 10-3 dm 3 Convert the followings to ml A. 800 L B cm 3

17 Measurement Density (d) = Mass (m) Volume (v) SI derived unit of density is kg/m 3 1 g/cm 3 = 1 g/ml = 1000 kg/m 3 1 g/ml = g/l

18 Example A piece of gold ingot with a mass of 301 g has a volume of 15.6 cm 3. Calculate the density of gold d = m V d = 301 = 19.3 g/cm A piece of platinum metal with a density of 21.5 g/cm 3 has a volume of 4.49 cm 3. What is the mass? m = d x V = 21.5 x 4.49 = 96.5 g

19 Example The density of Hg is 13.6 g/ml. Calculate the mass of 5.50 ml of liquid. 2. The density of sulfuric acid is 1.41 g/ml. Calculate the mass of 242 ml.

20 Measurement Temperature 273 K = 0 C 373 K = 100 C 32 F = 0 C 212 F = 100 C

21 Equations: transformation between units of temperature 9 F = x C C = 5 x ( F 32) 9 K = C

22 Example A certain solder has a melting point of 224 C. What is the melting point in F? F = 9 x C F = 9 x = 435 F 5 2. Helium has a boiling point of -452 F. Convert F to C. 5 C = x ( F 32) 9 5 C = x ( ) = -269 C 9 3. Mercury melts at C. convert it to kelvin K = C = = k

23 Examples 1. Which of the following is not an SI base unit? A) Kilometer B) kilogram C) second D) kelvin 2. Which of the following SI base units is not commonly used in chemistry? A) kilogram B) kelvin C) candela D) mole 3. Which of the following prefixes means 1/1000? A) kilo B) deci C) centi D) milli

24 Example 4. What temperature is 95 F when converted to degrees Celsius? A) 63 C B) 35 C C) 127 C D) 15 C 5. What temperature is 37 C when converted to kelvin? A) 310 K B) 99 K C) 236 K D) 67 K 6 What temperature is 77 K when converted to degrees Celsius? A) 296 C B) 105 C C) 196 C D) 25 C

25 Example 7. What is 22.6 m when converted to decimeters? A) dm B) 2.26 dm C) 226 dm D) 2.26 x 10 3 dm 8. What is 25.4 mg when converted to kilograms? A) 2540 kg B) 2.54 x10 5 kg C) 2.54 kg D) 2.54 x 10 4 kg