Name: _____________________________________________ Period: _______________Honors Chemistry Spring Final Review Packet 2019

Directions: Complete all of the following questions. Turn this in on the day of your final and you can earn up to 10 bonus points on your final. You must answer every questions in order to receive the bonus points. All answer must be hand written and you MUST show ALL work. You do not have to write in complete sentences and you do not have to rewrite the questions. This packet will be checked for both completion and accuracy.

Unit 9: Stoichiometry- Include a BALANCED CHEMICAL EQUATION and SHOW ALL WORK for credit.1) What is a mole?2) What is stoichiometry?3) What is the first step to all stoichiometry problems?4) What is the mole ratio?5) What is a limiting reactant?6) What is an excess reactant?7) How do you determine the limiting reactant?8) How do you determine how much excess remains? 9) Explain why the following statement is false: The limiting reactant is ALWAYS the react that you start with less of. 10) Calcium perchlorate decomposes to produce calcium chloride and oxygen gas. What volume of oxygen gas can be

produced if 390.0 g of calcium perchlorate decompose at STP? 11) Hydrogen gas and oxygen gas combine for form water vapor forms. If 74.3 L of water vapor are produced, how

many grams of hydrogen gas was used?12) How many moles of carbon monoxide must react with oxygen to produce 60.0g of carbon dioxide gas?13) Aqueous iron (III) chloride reacts with solid zinc to produce solid iron and a solution of zinc chloride in a single

replacement reaction. What mass of solid iron is produced from 0.29 g of solid zinc?14) Propane gas (C3H8) is burned in oxygen gas to produce carbon dioxide and water. What volume of oxygen gas is

needed to react with 4.50 x 1030 molecules of propane gas? 15) 1.22L of hydrogen gas reacts with 10.50L of chlorine gas to produce aqueous hydrochloric acid.

a. How many moles of HCl are produced?b. Identify the limiting reactant and excess reactant.c. What volume of excess reactant remains?d. If only 0.050 moles of HCl are produced in lab, what is the percent yield of the experiment? Is this

efficient?16) When 15.87g of manganese (II) hydroxide reacts with 12.84g of nitric acid liquid water and manganese (II) nitrate

are produced. a. What mass of water is produced?b. Identify the limiting reactant and excess reactant.c. What volume of excess reactant remains?d. What is the percent yield if 3.00g of water are produced in lab? Is this efficient?

17) When 43.5 g of CuO are exposed to 15.0 g of H2 copper metal and water are produced. a. What mass of water is produced?b. Identify the limiting reactant and excess reactant.c. What volume of excess reactant remains?d. What is the percent yield if 8.80g of water are produced in lab? Is this efficient?

Unit 10: Solutions- Answer all of the following questions. SHOW ALL WORK for credit.18) Explain the phrase “like dissolves like”. Give an example and a non-example. 19) What are 3 ways solutions can be separated? What type of solution is best for each separation technique? 20) What piece of glassware is used for making solutions?21) What piece of glassware is used to measure an amount of volume? 22) What two pieces of glassware is used to hold or mix chemicals? 23) What substance is the universal solvent and how did it get this nickname?24) Give an example of a solution and describe the solute and solvent. 25) Explain the terms solubility, soluble, and insoluble.

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26) What is concentration and why is it important?27) What are two ways to measure concentration experimentally? 28) Describe the process of LiBr dissolving in water. Be detailed and specific. 29) If you were making a solution of lemonade and you wanted the solute to dissolve faster, list at least 3 different

things you could increase the rate of dissolution.30) What is a colligative property?31) What property are colligative properties dependent on?32) What is a van’t Hoff factor?33) List 2 examples of colligative properties.

Use the solubility curve to answer questions 34-40. 34) What mass of each solute will dissolve in 100mL of

water at the following temperatures? a. NaNO3 at 10°C = __________________b. NaCl at 100°C= __________________c. K2Cr2O7 at 50°C= __________________d. Which of the above three substances is most

soluble in water at 15°C? _________________35) Which of the substances (if any) on the solubility curve

gases? How do you know?36) How much KCl can be dissolved in 500 g of H2O at 40oC? 37) A mass of 5.7 g of KClO3 is dissolved in 100 g of water at 30

ºC. The solution is heated to 70ºC. How many more grams of potassium chlorate must be added to make the solution saturated?

38) A solution of KNO3 is saturated in 100 g of water at 50 ºC. The solution is cooled to 40ºC to become supersaturated. How much excess KCl is dissolved in solution?

39) Is a solution that contains 60g of Pb(NO3)2 at 30°C (in 100 mL H2O) saturated, unsaturated, or supersaturated?40) Is a solution that contains 30g of KClO3 at 70°C (in 100 mL H2O) saturated, unsaturated, or supersaturated?

41) What is the molality of a solution made by dissolving 23.2 g of hydrofluoric acid in 500.0 g of water?42) What is the molar concentration of 15.0 g of KCl dissolved in 550. mL of solution?43) How many grams of silver sulfide must be dissolved in 425 grams of water to make a 0.520 m (molal) solution?44) Calculate the molarity of 50.0 grams of sugar, C12H22O11 in 500. mL of solution.45) What mass of solvent must be added to 17.3 g of lithium chloride to make a 0.115 m (molal) solution?46) 25 g of sucrose (C12H22O11) are added to 1550g of water. Find both the molality and the mole fraction of sucrose.47) Calculate the molarity of a solution prepared by dissolving 6.80 grams of CaSO4 in enough water to make 2.50

liters of solution. 48) What volume of solvent is required to prepare of 0.870 M CaCl2 using 5.7 g of CaCl2? 49) Calculate the volume of a 0.25 M solution of HCN made from 14.3 grams of HCN. 50) Your teacher asks you to prepare 30.0 mL of a 0.75 molar solution of NaCl for a lab. Write a step-by-step

procedure describing how you would carry out this task.51) If 70.0 mL of a 0.33 M sodium carbonate solution reacts with excess calcium chloride solution, what mass of

calcium carbonate precipitates out of solution? ___CaCl2(aq) + ___Na2CO3(aq) ___CaCO3(s) + ___NaCl(aq)52) A chemist reacts 75.0 mL of 0.200 molar calcium chloride solution completely with an excess of 0.750 M sodium

carbonate solution. What volume of sodium carbonate solution is needed?53) What is the limiting reactant if 0.50 L of 0.50 M potassium acetate solution is mixed with 0.50 L of 0.50 mol/L

copper (II) sulfate solution?54) For each set of solutions below, indicate which would how a higher boiling point AND which would have a higher

freezing point.a. A 0.50M solution of sodium chloride water or a 1.0M solution of sodium chloride water: Higher boiling

point? Higher freezing point?b. A 1.0 M solution of sugar water or a 1.0M solution of calcium chloride water: Higher boiling point? Higher

freezing point?

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55) How will adding 200mL of solvent to a 0.10M solution of salt water affect (Increase or Decrease)…?a. Concentration? B. Boiling Point? C. Freezing Point?

56) How will adding 15.0g of sodium chloride to a 0.10M solution of salt water affect (Increase or Decrease) …?a. Concentration? B. Boiling Point? C. Freezing Point?

57) Calculate the freezing point and boiling point for a 0.80 m aqueous solution of magnesium acetate. K f = 1.855 and Kb = 0.512

58) For a 1.80 m solution of sulfuric acid in water, calculate the freezing point and the boiling point of the solution. The Kf = 1.855 and the Kb = 0.512.

59) Using colligative properties, in complete sentences explain why we add antifreeze to the solution in our engines in the winter time. Discuss concentration, freezing point, and importance of antifreeze.

60) Describe the step-by-step process of diluting 850 mL of a 1.5M solution of NaCl to create 1500 mL of a 0.50M solution of NaCl.

61) During the dilution, what happens (Increase – Decrease – Remain the same) to the following: a. The concentration? B. The volume of the solution? C. The amount of solvent? D. The amount of solute?

62) Create a model before and after a dilution. Include a key showing the solute and solvent. 63) If 450 mL of water is added to 250mL of a 1.75 M K2SO4 solution, what will the molarity of the diluted solution be?64) If water is added to 350 mL of a 0.25 M KOH solution until the volume is 400. mL, what will the molarity of the

diluted solution be?65) How much 0.65 M NaCl solution can be made by diluting 0.70 L of 0.90 M NaCl?66) If 550mL of a 0.850 M KCl solution are set aside an allowed to evaporate until the volume of the solution is 230

mL, what will the molarity of the solution be?Unit 11: Acids and Bases- Answer all of the following questions. SHOW ALL WORK for credit.

67) List the 7 strong acids and 8 strong bases. 68) Compare and contrast properties of acids and bases.69) Give an example of a diprotic acid. 70) When describing an acid or a base, what do the terms strong and weak mean?71) What is the difference between Arrhenius’s definition and Bronsted-Lowry’s definition of acids and bases?72) What is an electrolyte? What type of substances are strong electrolytes? Weak electrolytes?73) What is a substance called that can act as an acid or a base? 74) What are the formulas for hydronium and hydroxide?75) Explain how you would determine the acid, base, conjugate acid, and conjugate base when given a reaction. Be

detailed. 76) If a substance has a high hydroxide ion concentration…

a. The substance is (ACIDIC/BASIC/NEUTRAL)b. The substance has a (HIGH/LOW/NEUTRAL) pHc. The substance has a (HIGH/LOW/NEUTRAL) pOH d. The substance has a (HIGH/LOW/NEUTRAL) hydroxide ion concentration.

77) What is a titration?78) Write the molecular equation, complete ionic equation, and net ionic equation for the following reactions. Be sure

to BALANCE all reactions AND include states of matter. Identify the spectator ions for each reaction.a. Molecular: ____Zn(OH)2 (aq) + ____HBr (aq) b. Complete Ionic:c. Net Ionic:d. Spectator Ions:

79) Write the molecular equation, complete ionic equation, and net ionic equation for the following reactions. Be sure to BALANCE all reactions AND include states of matter. Identify the spectator ions for each reaction.

a. Molecular: ____Ca(OH)2 (aq) + ____HCl (aq) b. Complete Ionic:c. Net Ionic:d. Spectator Ions:

80) Using Arrhenius’s definition identify the following as Acid, Base, or Salt: 3

a. HF b. KC2H3O2 c. AgOH d. H2SO4

81) For the following equations, label the Bronsted-Lowry acid/base AND label the conjugate acid and conjugate base. a. H2O +

_______________Br−

_______________ HBr +

_______________OH−

_______________b. HNO3 +

_______________H2O

_______________ H3O+ +

_______________NO3

−

_______________c. ClO4

− +_______________

H2O_______________

OH− +_______________

HClO4

_______________82) What is the pH of a 0.00567 M H2SO4 solution?83) What is the pOH of a 1.89 x 10−4 M HCl solution?84) What is the [H3O+] of a 6.2 x 10−5 M Ca(OH)2 solution? 85) What is the [OH−] of a solution with a pH of 5.67? 86) Determine if the following acids and bases are strong or weak. Then what kind of salt (acidic, basic,

neutral, or unable to determine) will be produced in a neutralization reaction between the following: Acid Base Type of salt produced (Acidic, Basic, or Neutral)

a. HClO3 (strong/weak) RbOH (strong/weak)b. HF (strong/weak) KOH (strong/weak)c. H2S (strong/weak) Mg(OH)2 (strong/weak)

87) What volume of 0.25 M barium hydroxide is needed to fully neutralize 70.0 mL of 0.75 M nitric acid?a. What would the pH be at the equivalence point for the titration above?

88) What volume of 1.50 M hydroiodic acid is needed to fully neutralize 450.0 mL of 0.60 M strontium hydroxide?a. What would the pH be at the equivalence point for the titration above?

Unit 12: Energy and Thermodynamics- Answer all of the following questions. SHOW ALL WORK for credit.89) What is energy?90) Define heat.91) Define temperature.92) Define enthalpy.93) Circle the correct answer: If something is (endothermic/exothermic) more heat goes from surroundings into the

system. The ΔH value is (positive/negative). 94) Indicate whether the following are endothermic (ENDO) or exothermic (EXO):

a. Combusting of propane D. Vaporizationb. When potassium iodide dissolve the beaker feels cold. E. Freezingc. C(s) + 2 F2(g) CF4(g) ΔHo = -680 kJ F. Sublimation

95) What is latent heat of fusion?96) True or false: Temperature always changes during a phases change97) Using specific heat explain why we use metals for things like pots and pans and covalent compounds for insulators.98) In calorimetry, where does the heat gained or lost by the system go?99) Answer the following questions based on the potential energy

diagram shown:a. This graph represent an (endothermic / exothermic)

reaction. b. Label the reactants, products, and activated complex.c. Draw a dashed line on the diagram to indicate a

potential energy curve for the reaction if a catalyst is added.

d. Determine the change in enthalpy, ΔH, for this reaction.

e. Determine the activation energy, Ea for this reaction. f. How much energy is required for this reaction to

occur? g. What is the ΔH for the reverse reaction?h. What is the activation energy for the reverse reaction?

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100) Sketch a potential energy curve below that is represented by the following values of ΔH and Ea (activation energy). You may make up appropriate values for the y-axis (potential energy). ΔH = +150 kJ and Ea = 75 kJ

101) How much energy will it take to raise the temperature of 175.0 g of water from 5.0oC to 85.0oC? (specific Heat = 4.184 J/(goC ))

102) How much heat must be gained absorbed to melt a 100.0 gram block of ice at 0°C? (ΔH fus = 3.35 x 105 J/kg)103) How much energy must be absorbed to heat a 150.0 g sample of water initially at room temperature (25oC) is

heated and vaporized until it reaches a temperature of 167oC. The specific heat capacity of steam is 2.03 J/goC, the specific heat capacity of water is 4.184 J/goC, the ΔHfus = 3.35 x 105 J/kg, and the ΔHvap = 2.26 x 107 J/kg.

a. Draw a heating curve for this problem. 104) A 15.0 g sample of ice initially at -15.0oC is heated and melted until it reaches a final temperature of 25oC. How

much heat was absorbed? The specific heat capacity of ice is 2.09 J/goC, the specific heat capacity of water is 4.184 J/goC, the ΔHfus = 3.35 x 105 J/kg, and the ΔHvap = 2.26 x 107 J/kg.

a. Draw a heating curve for this problem. 105) A piece of metal weighing 55.5 g was heated to 115oC and then put into a calorimeter containing 100.0 g of

water that is at an initial temperature of 25.0oC. The metal and water were allowed to come to an equilibrium temperature determined to be 19.8oC. Assuming no heat was lost to the environment, calculate the specific heat of the metal. Water has a specific heat of 4.184 J/goC.

106) A 2.0 gram sample of potassium nitrate was dissolved into a calorimeter containing 50.0 grams of water. The temperature of the water decreased from 45.0oC to 25.4oC. Water has a specific heat of 4.184 J/goC. Calculate the amount of energy that was absorbed by the potassium nitrate (qsystem).

107) Find ΔH° for the reaction C2H5OH (l) + 2 O2 (g) 2 CO2 (g) + 2 H2O (l), using the following data.

2H2(g) + 2C(s) + O2(g) C2H5OH(l) ΔH = -485.62 kJ

C (s) + O2 (g) CO2 (g) ΔH = -394.51 kJ

H2 (g) + ½ O2 (g) H2O (l) ΔH = -285.8 kJ

108) Calculate ΔH for the reaction N2 (g) + 3 H2 (g) 2 NH3 (g), from the following data:

N2 (g) + O2 (g) 2 NO (g) ΔH = -180.5 kJ

4 NH3 (g) + 5 O2 (g) 4 NO (g) + 6 H2O (g) ΔH = -1628.2 kJ

2 H2 (g) + O2 (g) 2 H2O (g) ΔH = -483.6 kJ

109) Use the given standard enthalpies of formation to determine the heat of reaction of the following reaction:

a. Li2CO3(s) + H2O(l) 2 LiOH(s) + CO2(g) b. C3H8 (g) + 5O2 (g) 3CO2 (g) + 4H2O (l)

110) How many kilojoules are given off when 20.0 g of Mg react?_____Mg(s) + _____O2 (g) → ____MgO(s) ΔH = −1,213 kJ

111) If 450.0 kJ of energy is absorbed, what volume of oxygen gas is produced at STP? _____SO3 (g) → _____SO2 (g) + O2 (g) ΔH = +197.9 kJ

112) NaHCO3 decomposes when exposed to heat. What mass of NaHCO3 is decomposed by 256 kJ? _____NaHCO3(s) → ____Na2CO3 (s) + ____CO2 (g) + _____H2O(l) ΔH = 91.5 kJ.

Unit 13: Gas Laws- Answer all of the following questions. SHOW ALL WORK for credit.113) What is the relationship between pressure and volume?

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114) What is the relationship between volume and temperature?115) What is the relationship between volume and number of moles?116) What is the relationship between pressure and temperature?117) What is the relationship between molecular speed and molar mass?118) What is the kinetic molecular theory?119) STP stands for ______________________ ______________________ ______________________. 120) At STP, the temperature is _________, the pressure is _________, and 1 mole of gas occupies _________ space. 121) What is pressure?122) What is temperature? 123) Why are gases sometimes collected over water?124) What is an ideal gas and give a real life example of an ideal gas?125) Label the following scenarios as describing DIFFUSION or EFFUSION of a gas.

a. _________________A truck tire runs over a nail and air slowly leaks out.b. _________________A popped pool floaty slowly leaks air. c. _________________The smell of freshly baked bread fills the kitchen and then through the entire house.

126) Which of the following is the lowest pressure? 1.57 atm, 785 mm Hg, 67 PSI127) If I have 4.0 liters of gas held at a pressure of 1.4 atm and a temperature of 290 K, how many moles of gas do I

have?128) If 18.6 moles of helium gas held at a pressure of 0.85 atm and a temp of 200.0 K, what is the volume of the gas?129) You are playing in the pool during a hot summer day. If you go down to the bottom of the pool where the

pressure is 2.25 atm and the temperature is 280 K and you blow an air bubble that is 3.50 mL. What size will the bubble be when it rises to the top of the pool that has a temperature of 295K and pressure of 1.0 atm?

130) If carbon monoxide and oxygen are in a container and exert a pressure of 890 torr, and the partial pressure of carbon monoxide is 640 torr, what is the partial pressure of oxygen?

131) A 4.8 liter balloon holding 0.65 moles of carbon dioxide leaks. If we are able to determine that 0.20 moles of carbon dioxide escaped before the container could be sealed, what is the new volume of the container?

132) A metal tank contains three gases: oxygen, helium, and nitrogen. If the partial pressures of the three gases in the tank are 3.5 atm of O2, 475 mm Hg of N2, and 19.0 PSI of He, what is the total pressure inside of the tank?

133) A 500.0 mL sample of carbon monoxide gas is collected over water at 5° C, and 780.0 mm Hg. What is the volume of the gas at STP?

134) Methane gas (C4H10) and propane gas (C3H8) are both released from a tank. Both of these gases are combustible. If a match was lit at 5 meters away from the tank, which gas would ignite first? Explain your answer.

135) A sample of gas occupies 0.30 L of space at -13 ˚C and 0.65 atm. How much space will the gas occupy at STP?136) How hot will a 0.83 L balloon have to get to expand to 1.40 L? Assume the initial temperature is 0◦C.137) A gas has a pressure of 909 mm Hg at 240.0 ˚C. What is the temperature at standard pressure?138) Pedro adds 0.25 moles of helium to a balloon that already contained 1.89 moles of helium creating a balloon

with a volume of 3.45 liters. What was the volume of the balloon before the addition of the extra gas? 139) Divers get “the bends” if they come up too fast because gas in their blood expands, forming bubbles in their

blood. If a diver has 0.05 L of gas in his blood under pressure of 2.50 atm, then rises instantaneously to a depth where his blood has a pressure of 1.0 atm, what will the volume of gas in his blood be?

140) The air pressure in my tires is about 33 psi on a day with the temperature around 45◦C. What will the pressure in my tires be on a cold day with a temperature of -10◦C?

141) A thermometer, which measures temperature by compressing and expanding of gas in a piston, has a volume of 20.0 L at 100◦C. What is the temperature outside if the piston has a volume of 15 L?

142) A reaction yielding helium gas produced 68.5 mL of gas collected over water at 278 K and 760.0 torr. What is the partial pressure of the gas under these conditions?

143) How many liters of oxygen gas are consumed if 3.00 g of hydrogen gas to produce water at STP?____ H2 (g) + ____O2 (g) ____H2O (g)

144) What volume of hydrogen gas is needed to react with excess nitrogen in order to produce 27.0 g of liquid ammonia at a 415 K and 0.800 atm? ____H2 (g) + ___N2 (g) ____NH3 (l)

145) How many liters of sulfur dioxide are produced from the reaction of elemental sulfur with 26.9L of oxygen?____S8 (s) + ____O2 (g) ____SO2 (g)

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146) When 4.50 g methane combusts at 273 K and 1.00 atm, what volume of carbon dioxide is produced?____CH4 (g) + ____O2 (g) ____CO2 (g) + ____H2O (g)

147) What mass of hydrobromic acid is produced when 43.5 L of bromine gas reacts with excess hydrogen gas at 305 K and 1.90 atm? ____Br2 (g) + ____H2 (g) ____HBr (aq)

Unit 14: Rates and Equilibrium- Answer all of the following questions. SHOW ALL WORK for credit.148) List 5 factors the affect the rate of a reaction:149) What is a reversible reaction?150) What is a homogeneous reaction?151) Using the collision theory explain why the rate of a reaction increases when temperature is increased. 152) What is chemical equilibrium? What is equal at chemical equilibrium? What is constant at chemical equilibrium?153) What do brackets [ ] indicate?154) What are the units of K? 155) What does a large K value indicate? What does a small K value indicate? What does a K value of 1 indicate?156) State LeChatelier’s Principle.157) What does it mean if a reaction shifts towards the products?158) Write the following equilibrium expression

a. 4 Al (s) + 3 O2 (g) 2 Al2O3 (g)b. 2 HI (aq) H2 (g) + I2 (g)c. 2 C2H6 (g) + O2 (g) 4 CO2 (g) + 6 H2O (g)d. 3 Li2S (aq) + 2 AlP (aq) Al2S3 (s) + 2 Li3P (aq)

159) At a given temperature, the Kc for the reaction below is 1.00 x 10-14. If the concentrations of hydroxide is 1.00 x 10-7 at equilibrium, find the concentration of hydronium. What does the K tell you about equilibrium for this reaction? H2O (l) H3O+ (aq) + OH− (aq)

160) What is the equilibrium expression and equilibrium constant if the equilibrium consists of 15.0g of NaOH, 0.75M HCl, 1.8 L H2O, and 1.25 M NaCl. What does the K tell you about equilibrium for this reaction?

NaOH (s) + HCl (aq) H2O (l) + NaCl (aq) 161) A closed system initially containing 0.850 M HI at 25oC is allowed to reach equilibrium. Analysis of the

equilibrium mixture shows that the equilibrium concentration of I2 is 0.220 M. Calculate K at 25oC for the reaction.2HI (g) H2 (g) + I2 (g)

162) Initially, 2.0 mol of NO (g) and 2.0 mol of Cl2 (g) were added to a 1.0 L container. As a result of the reaction, the equilibrium concentration of NOCl (g) became 1.40 M. determine the equilibrium constant for the reaction and complete the ICE table. 2 NO (g) + Cl2 (g) 2NOCl (g)

163) Using LeChatelier’s principle, list at least 3 ways to increase amount of oxygen gas in the following reaction: 2 S(s) + 3 O2(g) 2 SO3 (g) ΔH = – 790.00 kJ

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164) Complete the following chart by writing left, right, or none for the equilibrium shift. Write decrease, increases, or remains the same for the concentrations of reactants and products.

Unit 15: Nuclear Chemistry- Answer all of the following questions. SHOW ALL WORK for credit.165) What is nuclear chemistry?166) Compare and contrast chemical reactions and nuclear reactions.167) Radioactivity is the process by which atoms give off _____________________ or _________________________. 168) What is radiation?169) What is the format for writing a nuclear symbol?170) What is a nuclide?171) What is an atom with a charge called?172) Isotopes are elements with the same # of _________________, but different __________________________.173) What are radioisotopes?174) What is half-life?175) Compare and contrast fusion and fission (at least 3 similarities and 3 differences). 176) Fill out the table below:

177) Complete the following nuclear equations: e. + __________

f. + + + __________

g. + __________

h. _________ + + +

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178) Write an equation for the decay of polonium-210, which produces two alpha particles, a beta and another substance.

179) Write the nuclear equation for the decay of Am-243 if it undergoes gamma decay accompanied with alpha and beta decay.

180) A 1600 g sample of 16N decays to 50 g in 36 seconds. What is its half-life?181) The half-life of Co-60 is 5.26 years. If 50g are left after 21.0 years, how many grams were in the original sample?182) How much of a 40.0 g sample of 222Ra if left after 12 days if its half-life is 4 days?183) How much of a 500g sample of U-238 is left after 8.94 x 109 seconds if the half-life of U-238 is 4.47 x 109

seconds?184) If 600g of I-131 decays to 75 g in 15 days, what is the half-life of Au-131? 185) What is the half-life of U-238 based on the graph below?

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VAPOR PRESSURE OF WATERTemperature (oC)

Pressure (mm Hg)

Temperature (oC)

Pressure (mm Hg)

5 6.5 55 118.010 9.2 60 149.415 12.8 65 187.520 17.5 70 233.725 23.8 75 289.130 31.8 80 355.135 41.2 85 433.640 55.3 90 525.845 71.9 95 633.950 92.5 100 760.0

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