CHM 2040 IA Final Review Spring 2018 Disclaimer: This guide should be utilized as a supplement to your studying and not entirely relied upon for your success. You are ultimately responsible for all the material covered in class and book readings assigned. It is your responsibility to verify the accuracy of the information of this sheet in the event of error. 1) Classify according to composition A). Oxygen gas B). Sand C). Bronze D). Calcium sulfate crystals 2) Define the processes A) Filtration B) Decanting C) Distillation 3) Classify based on physical change, chemical change, physical property and chemical property. A) Smell of camphor B) Burning magnesium ribbon in air C) Sublimation of dry ice D) acidity of lemon E) Stretching of copper wire 4) Convert -78 O C TO O F? 5) Find the number of significant figures? A). 1.7 g B). 0.000054600 g C). 320.g D). 1.006g E). 120000g 6) Write the following in scientific notation with respective significant figures A). 3456123 g (4 SF) B) 0.00043757 m (3 SF)
7) When a copper block of mass 50.0g dropped into a beaker of water, the level of water raised from 32.0ml to 40.5mL. Find the density of the copper block. 8) Which will displace smaller volume of water, when you place 20.0g of iron block with density 7.86g/cm^3 or an aluminum block of mass 20g with density 2.70g/cm^3? A). Iron block B). Aluminum block 9) Following are the mass of a 12.0g glass block weighed by four groups in consecutive trials. Which group has the precise and accurate measurement? A). 8.9g, 9.0g, 13.1g, and 12.9g Avg= 11.0g B). 10.9g, 11.6g, 14.7g and 10.5 g; Avg= 11.9g C). 9.6g, 9.8g, 9.3g and 9.4g; Avg; 9.5g D). 12.3g, 11.9g, 12.1g and 12.2; Avg=12.1g 10) Find the number of protons, neutrons and electrons in the following A) Ra-227 B) 14 N 7 C) 208 Pb 82 11) The number of electrons and protons present in the following A) Mn +5 B) S -2 C) Zn +2 D) Br -1 12) Galium has two naturally occurring isotopes. Ga-69 is 68.92558 amu with relative abundance of 60.108%. Ga-71 is 70.92470 amu. Find the average atomic mass. 13) The average atomic mass of Cu is 63.55amu. Cu-65 with a mass of 64.9278 amu has an abundance of 30.83%. What will be the mass of the other isotope Cu-63? 14) Calculate the number of atoms in 526.0g of pure Iron block (Fe-55.85g/mol)
15) 14. Classify the following as ionic or molecular compounds A) CaCl2 B) H2S C) CaSO4 D) N2O5 E) NH4NO3 16) Name the compounds: a. NaCl b. CuCl2 c. CaSO4 d. (NH4)2CO3 e. FePO4 f. NO2 g. N2O5 h. H3PO4 i. H Cl j. H NO3 17) Write the Chemical formula a. Iron (III) hydroxide b. Aluminum oxide c. Ammonium sulfate d. Potassium iodide e. Lead (II) sulfate f. Potassium chlorate g. Diphosphorus pentoxide
h. Dihydrogen dioxide i. Silicon hexachloride j. Diphosphorus monobromide k. Selenium trioxide l. Tribismuth heptafluoride 18) The elemental mass percent composition of ibooprufen is 75.69% C, 8.80% H, and 15.51% O. Determine the empirical formula and molecular formula if the molecular mass of ibuprofen is 206.29 g/mol 19) A) What is the percentage of composition of oxygen in CaSO4 [CaSO4-136.14g/mol] B) The mass (in grams) of calcium present in 354g of CaSO4 20) Balance the following equations A) Na2S(aq) + CuNO3(aq) --------> NaNO3(aq) + CuS(s) 21) What is the percentage of yield if the reaction between 8.9g of nitrogen gas and 4.6 g of hydrogen gas produced 8.4g of ammonia? a. N2 (g) + H2 (g) 2 NH3 (g) 22) How much grams of lithium nitrate must be dissolved to get a 300.0mL 2.5M aqueous solution? 23) What will be the concentration of the aqueous solution prepared by dissolving 6.50g of calcium carbonate in water and made it up to 250mL? 24) What will be the final concentration if 45mL of 2.5M HCl is diluted up to 150mL 25) 50.0mL of 0.25M Pb(NO3)2 reacted with 75.0mL of 0.1M HCl. The reaction is as follows; a. Pb(NO3)2(aq) + 2HCl(aq) PbCl2(S) + 2HNO3 (aq) A) Write the complete and net ionic equation. B) If the mass of PbCl2 formed were 0.86g. What is the percentage of yield of the reaction. [ Pb(NO3)2-331.2g/mol, HCl-36.46g/mol, PbCl2-278.1g/mol]
26) Which of the following is insoluble? A). LiNO3 B). BaS C). PbSO4 D). (NH4)2CO3 27) What will be the change in internal energy if a system releases about 386 kj energy and the surrounding does about 190kJ of work on the system? 28) Find the work associated with the expansion of a system at 5.6L to 7.9L against an external pressure of 2.5atm in joules. 29) Consider 50.0g of iron Nickel block and 50.0mL of water, both initially at 25.0 0 C. If we heat them separately by applying 1200.0J of energy. [Specific heat capacities Ni= 0.44 J/g 0 C Water= 4.184 J/g 0 C] A) Which one will have highest final temperature. B) Which one will have the lowest change in temperature. C) With the same amount of samples, for which sample we have to provide highest amount of energy for a 20.0 0 C temperature change. 30) 12.06g of C6H12O6 reacted with excess oxygen in a bomb colorimeter with heat capacity 1.56J/0C. What will be the enthalpy change for the following reaction if the temperature of the colorimeter changed by 30.0 0 C? [ molar mass of C6H12O6 is 180.156g/mol] C6H12O6(s) + 9O2(g) --------> 6CO2(g) + 12H2O(g) 31) When 3.45g of Zn reacted with enough HCl in a coffee cup calorimeter the temperature of the 60.mL solution changed by 1.6 o C. Find the enthalpy of the reaction as written. [Use 1.0g/mL as density of the solution and 4.184 J/g o C as the heat capacity] Zn(s) + 2HCl(aq) --------> ZnCl2(aq) + H2g) 32) Given the following thermochemical equations: a. I) N2 (g) + O2 (g) 2 NO (g) H = 180.6 kj b. II) N2 (g) + 3 H2 (g) 2 NH3 (g) H = -91.8 kj c. III) 2 H2 (g) + O2 (g) 2 H2O (g) H = - 483.7 kj Calculate H for the following reaction: 4 NH3 (g) + 5 O2 (g) 4 NO (g) + 6 H2O (g)
33) Find the ΔH for the reaction below using the standard enthalpy of formation 3NO2 (g) + H2O(l) 2HNO3(aq) + NO (g) a. NO2 (g) ΔHf = 33.2 kj/mol b. H2O(l) ΔHf = -285.8 kj/mol c. HNO3 ΔHf = -207 kj/mol d. NO(g) ΔHf = 91.3 kj/mol