1. The Basics Reminders about simple terms and concepts. Zumdahl Chapter 3

2. Equations Zn + H + + Cl - ----> Zn 2 + + Cl - + H 2

3. Equations Zn + 2H + + Cl - ----> Zn 2 + + Cl - + H 2

4. Equations Zn + 2H + + 2Cl - ----> Zn 2 + + 2Cl - + H 2

5. Equations Zn + 2H + + 2Cl - ----> Zn 2 + + 2Cl - + H 2 Zn + 2(HCl) ----> Zn 2 + + 2Cl - + H 2

6. Equations Zn + 2H + + 2Cl - ----> Zn 2 + + 2Cl - + H 2 Zn + 2(HCl) ----> Zn 2 + + 2Cl - + H 2 Zn + 2H + ----> Zn 2 + + H 2

7. Equations Zn + 2H + + 2Cl - ----> Zn 2+ + 2Cl - + H 2 Zn + 2(HCl) ----> Zn 2+ + 2Cl - + H 2 Zn + 2H + ----> Zn 2 + + H 2 Zn (s) + 2H + (aq) ----> Zn 2 + (aq) + H 2(gas)

8. Equations Zn (s ) + 2H + (aq) ----> Zn 2 + (aq) + H 2(gas) - means that on an atomic ratio, 1 Zn atom reacts with 2 H + ions to produce 1 Zn 2+ ion and 1 hydrogen diatomic molecule. - we don’t work on an atomic scale very often so we define a new unit which is a bunch of atoms or molecules. - we don’t count atoms very often so we work in the mass of that bunch.

9. Moles and Molar Masses The ‘bunch’ I alluded to earlier is the number of atoms contained in exactly 0.0120000 kg of carbon which contains only the 12 C isotope. ( 6 protons + 6 neutrons in the nucleus.) We call this unit the MOLE. 1 mole is 6.023 x 10 23 particles Avogado Number.

10. Moles and Molar Masses Thus the MOLAR MASS is just the mass of a mole of any particular substance. May also be referred to as the atomic or molecular weight. H = 1.0079 g / mol = 0.0010079 kg / mol CO 2 = 44.009 g / mol = 0.044009 kg /mol Conceptually, this allows us to compare and calculate relative amounts of material.

11. Stochiometry Zn + 2(HCl) ----> Zn 2 + + 2Cl - + H 2 one mole of zinc metal reacts with two mole of hydrogen chloride to produce one mole of zinc ions two moles of chloride ions and one mole of hydrogen gas. 65.39 g Zn + 72.92 g HCl ----> 65.39 g Zn 2 + + 70.91 g of Cl - + 2.01 g of H 2

12. IDEAL GASES Zumdahl, Chapter 5

13. Basic Definitions Amount in moles ( mol ) Pressure in Pascals ( N m -2 ) Volume in metre 3 ( m 3 ) Temperature in Kelvin ( K )

14. Pressure Pressure = force / area = Newtons / metre 2 = Pascals.

15. Pressure Pressure = force / area = Newtons / metre 2 = Pascals Standard atmospheric pressure = 101 325 Pascals

16. Pressure Pressure = force / area = Newtons / metre 2 = Pascals Standard atmospheric pressure = 101 325 Pascals This is equivalent to 1.000 atm or a pressure that will support a column of mercury 760 mm tall in a barometer.

17. Volume Measured in metre 3 which may not be convenient. More common to use litres but : 1 L = 0.001 m 3

18. Temperature We need an absolute temperature scale. i.e. one for which zero means something. We use the Kelvin scale on which ice melts at 273.2 K or 0K is -273.2 o C.

19. Boyle’s Law volume is proportional to 1 / pressure P 1 V 1 = P 2 V 2 For a fixed amount of gas at constant temperature.

20. Charles’ Law Volume is proportional to absolute temperature V 1 / V 2 = T 1 / T 2 For a fixed amount of gas at constant pressure.

21. V T o C -2730 He N2N2

22. Equation of state PV = n RT R = 8.3145 Nm mol -1 K -1 = 8.3145 J mol -1 K -1 For an ideal gas.

23. Equation of state PV = n RT If you know any three of P, V, n, and T, you can calculate the fourth. What is the volume occupied by 2.30 moles of helium at 313 K and 217 kPa?

24. What is the volume occupied by 2.30 moles of helium at 313 K and 217 kPa? V = n R T / P V = 2.30 mol x 8.31 Nm mol -1 K -1 x 313 K / 217 x 10 3 Nm -2 V = 0.0276 m 3

25. What is the volume occupied by 2.30 moles of helium at 313 K and 217 kPa? V = n R T / P V = 2.30 mol x 8.31 Nm mol -1 K -1 x 313 K / 217 x 10 3 Nm -2 V = 0.0276 m 3 DOES THIS MAKE SENSE??????????