REVIEW – Chapters 1 – 9 A. Consider the metal sodium. 1. How many grams are there in 0.100 mole? 2. How many atoms are there in 1.00 g? 3. How many moles are there in 3.76 g? 4. Compare sodium to potassium and magnesium with respect to a. Atomic radius b. Ionization energy c. electronegativity 5. Compare Na to Na+ with respect to size. 6. Write the electron configuration and orbital diagram for sodium. 7. Sodium D-line has a wavelength of 589 nm. Calculate: a. Its frequency. b. ∆E in kJ/mol. B. When sodium is added to water (d = 1.00 g/mL), the following reaction occurs: 2Na(s) + 2H2O(ℓ) → 2Na+(aq) + 2OH-(aq) + H2(g) 1. How many grams of sodium will react with 10.0 mL of water? 2. Five grams of sodium are added to 25.00 mL of water at 20˚C. Assume 100% yield for the next 4 questions (a-d). a. What is the limiting reactant? b. How many grams of H2 are produced? c. What are the masses of the reactants after the reaction is complete? d. What is the molarity of Na+ produced? What is the molarity of OH- produced? e. If only 0.100 g of H2 is produced, what is the percent yield? f. What volume of H2 will be produced at 20˚C if the gas is collected over water (vp = 17.54 mm Hg)? The barometric pressure is 754.6 mm Hg g. What is the mass of a gas that will effuse ¼ times as fast as H2? 3. Calculate ∆H˚ for the reaction. 4. If 1.00 g of sodium and an excess of water reacted, how much heat will be evolved? 5. If the reaction is done in a bomb calorimeter (heat capacity = 9.33 kJ/˚C) using 2.50 g of sodium and an excess of water, what is the final temperature of the system if its initial temperature is 20.00 ˚C? C. Write balanced net ionic-equations using smallest number coefficients to represent the reactions between aqueous solutions of the following compounds. 1. Sulfuric acid and sodium hydroxide.2. Sodium hydroxide and iron (III) nitrate. 3. Hypochlorous acid and potassium hydroxide. 4. Ammonia and perchloric acid. 5. Sulfite ions in a basic solution with solid cobalt (III) hydroxide to give sulfate ions and solid cobalt (II) hydroxide. 6. Dichromate ions in an acidic solution with iodide ions to form chromium (III) ions and triodide (I3-) ions. D. Consider the reaction between aqueous solutions of scandium (III) chloride and silver (I) sulfate. 1. How many mL of 0.0750 M silver sulfate is required to react completely with 200.0 mL of 0.120 M scandium (III) chloride? 2. How many grams of precipitate can be theoretically obtained? E. Consider water at 20 ˚C. Its density is 1.00 g/mL, its vapor pressure at 20˚C is 17.54 mm Hg. Five grams are poured into a 20.0 L flask. 1. Would all the water vaporize? 2. If not how much would vaporize? 3. Calculate the heat of vaporization for water. F. Substance Y has a vapor pressure of 120 mm Hg at 25˚C. 1. It is put into a 20.0 L tank at 25˚C. The pressure in the tank is measured to be 100 mm Hg at the same temperature. What phase(s) of Y is/are in the tank? 2. Substance Y is transferred (without loss of contents) at the same temperature to a 10.0 L tank. What is the pressure in the tank after equilibrium is reached? What phase(s) of Y is/are in this tank? 3. If 0.0100 mol of substance Y are put into 2.00 L tank at 25˚C, what phase(s) of Y is/are in the tank after equilibrium? G. An unknown substance X has a vapor pressure of 158 mm Hg at 25˚C. Its normal boiling point is 73˚C. Its triple point is 5˚C, 70 mm Hg. The density of the solid is 1.12 g/cm3, while that of the liquid is 0.98 g/cm3. Its critical temperature is 100˚C while its critical pressure is 1534 mm Hg. 1. Draw the phase diagram for X. 2. label the solid, liquid, and gas regions. 3. Label the triple point with the letter A. 4. Label the critical point with the letter B. 5. Draw a solid arrow across the curve crossed when X melts. 6. Draw a dashed arrow across the curve crossed when X sublimes. 7. Draw a crooked arrow ( ) across the curve crossed when X condenses. 8. Calculate ∆Hvap of X. Do not use the critical point or the triple point in your calculations.ANSWERS A. 1. 2.30 g 2. 2.62 x 1022 atoms 3. 0.163 mol 4. a) Na<K, Na>Mg b) Na>K, Na<Mg c) Na>K, Na<Mg 5. Na>Na+ 6. 1s2 2s2 2p6 3s1; (↑↓) (↑↓) (↑↓)(↑↓)(↑↓) (↑) 1s 2s 2p 3s 7. a) 5.09 x 1014 s-1 b) 203. 1 kJ/mol B. 1. 12.8 g 2. a) Na b) 0.220 g c) Na = 0.00 g; H2O = 21.08 g d) Na+ = OH- = 10.3 M e) 45.5 % f) 2.70 L g) 32.0 g/mL 3. -368.6 kJ 4. 8.01 kJ 5. 22.15 ˚C C. 1. H+ (aq) + OH- (aq) → H2O 2. OH- (aq) + Fe3+ (aq) → Fe(OH)3 (s) 3. HCℓO (aq) + OH- (aq) → CℓO- (aq) + H2O 4. NH3 (aq) + H+ (aq) → NH4+ (aq) 5. SO32- (aq) + 2Co(OH)3 (s) → SO42- (aq) + 2Co(OH)2 (s) + H2O 6. Cr2O72- (aq) + 9I- (aq) + 14H+ (aq) → 2Cr3+ (aq) + 3I3- (aq) + 7H2O D. 1. 4.80 x 102 mL 2. 103 g E. 1. no 2. 0.344 g 3. 42.8 kJ/mol F. 1. gas2. 120 mm Hg; liquid and gas 3. gas G. 1. -7 see below 8. .28.0