Lecture_Notes_101209a

Lecture_Notes_101209a - forming the products y How do we...

Info iconThis preview shows pages 1–12. Sign up to view the full content.

View Full Document Right Arrow Icon
Calorimetry y A 275 mL sample of water at 55.2 o C is in a coffee cup calorimeter. What are the final temperatures when each of the following things at 25.0 o C are added to the hot water? s H2O = 4.18 J/ o C*g, d H2O = 1.00 g/mL y A steel ball, 2.20 cm diameter. d = 7.83 g/mL, s = 0.45 J/ o C*g
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
A 5 mL sample of water 5 . 2oC 4 7o C 25.0 o 40.1oC 10% 4% 4% 82% 1. 55.2 o C 2. 54.7 o C 3. 25.0 o C 4. 40.1 o C
Background image of page 2
Enthalpies of Formation y Enthalpy of formation- the change in enthalpy that accompanies the formation of one mole of a compound. y Rationale- Enthalpy has no absolute value, it is relative to the elements making up the compound. We measure heat of formation from the elements in their standard states at T = 298 K and P = 1.00 atm.
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Standard States y Compound- for a gas it is 1.0 atm of pressure, for a solution it is exactly 1M, for a pure substance (liquid or solid) it is a pure liquid or solid y Elements- the form in which it is the most stable at 1 atm and 25 o C.
Background image of page 4
Enthalpy of Reaction y Definition- the enthalpy change of the reactants
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Background image of page 6
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Background image of page 8
Background image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Background image of page 10
Background image of page 11

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Background image of page 12
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: forming the products. y How do we calculate? Combustion of Methane Thermite Reaction Properties of Enthalpy of Reaction y Extensive Property-y Reversibility-y Depends on Physical State-y Additivity-Hess’s Law N 2 + O 2 2NO N 2 O + (1/2)O 2 190.74 kJ-99.20 kJ H Hess’s Law Hess’s Law y Determine the enthalpy change for the oxidation of ammonia: { 4 NH 3 (g) + 5 O 2 (g) → 4 NO (g) + 6 H 2 O (l) { From the following data: N 2 (g) + 3 H 2 (g) → 2 NH 3 (g) ∆ H = -99.2 kJ N 2 (g) + O 2 (g) → 2 NO (g) ∆ H = +180.5 kJ 2 H 2 (g) + O 2 (g) → 2H 2 O (l) ∆ H = -571.6 kJ Hess’s Law y Calculate the enthalpy for the reaction: { BrCl (g) → Br (g) + Cl (g) { By using the following data: Br 2 (l) → Br 2 (g) ∆ H = 30.91 kJ Br 2 (g) → 2 Br (g) ∆ H = 192.9 kJ Cl 2 (g) → 2 Cl (g) ∆ H = 243.4 kJ Br 2 (l) + Cl 2 (g) → 2 BrCl (g) ∆ H = 29.2 kJ...
View Full Document

{[ snackBarMessage ]}

Page1 / 12

Lecture_Notes_101209a - forming the products y How do we...

This preview shows document pages 1 - 12. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online