CHM 130: Final Eam Practice Problems 1. Complete the following table: Isotope Mass number # of protons # of neutrons # of electrons strontium-90 90 38 5 38 neon-19 19 10 9 10 iron-55 55 6 9 6. Consider Figures A-F below: A B C D E F Indicate the figure represented as an element, a compound or a miture AND a solid, a liquid or a gas. A. element compound miture solid liquid gas B. element compound miture solid liquid gas C. element compound miture solid liquid gas D. element compound miture solid liquid gas E. element compound miture solid liquid gas F. element compound miture solid liquid gas CHM 130 Final Eam Practice Problems Key page 1 of 6
3. Circle all of the following changes that are chemical: vaporizing fizzing subliming precipitating burning rusting condensing 4. Indicate the symbol for the element that fits each of the following descriptions: Xe F Mg Fr Sc Y a. The noble gas in the fifth period. b. The halogen with the greatest ionization energy. c. The alkaline earth metal in the third period. d. The alkali metal with the greatest metallic character. e. The transition metal in the fourth period with the lowest atomic number. f. The transition metal in the fifth period with the largest atomic radius. 5. A 6.5 g of sodium hydrogen carbonate is mied with.709 g of hydrochloric acid to produce 4.348 g of sodium chloride, 3.73 g of carbon dioide, and water. What mass of water forms? 6.5 +.709 g = 8.961 4.348 3.73 g = 1.340 g (all to 3 decimal places!) 6. A 5.00 g sample of piece of titanium is placed in a graduated cylinder containing 3.56 ml of water. If the density of titanium is 4.51 g/cm 3, what is the new level of the water after the piece of titanium is added. ml 5.00 g Ti = 5.54 ml 4.51 g Ti 5.54 ml + 3.56 ml = 9.10 ml (to decimal places) 7. For each the following compounds, indicate whether it is ionic (I) or molecular (M),and give the corresponding name or formula: I or M M a. nitric acid HNO 3 (aq) I b. zinc phosphate Zn 3 (PO 4 ) I c. silver nitride Ag 3 N I d. ammonium chromate (NH 4 ) CrO 4 M e. HC H 3 O (aq) acetic acid I f. SrF strontium fluoride M g. H S(aq) hydrosulfuric acid M h. N O 5 dinitrogen pentaoide I i. Sn(CO 3 ) tin (IV) carbonate I j. CoN cobalt (III) nitride CHM 130 Final Eam Practice Problems Key page of 6
8. For each of the following, i. Identify the type of reaction using the letters designated below: Combination (C) Double Replacement/Precipitation (DR) Decomposition (D) Neutralization (N) Single Replacement (SR) Combustion (B) TYPE ii. Balance the equation SR A. Na (s) + H O (l) H (g) + NaOH (aq) DR B. Fe (SO 4 ) 3 (aq) + 6 LiOH (aq) Fe(OH) 3 (s) + 3 Li SO 4 (aq) B C. C 5 H 6 O (l) + 6 O (g) 3 H O (g) + 5 CO (g) D D. H 3 BO 3 (s) B O 3 (s) + 3 H O (l) 9. For each of the following sets of reactants, write the formulas for the products and balance the equation if the reaction occurs, or write NR for no reaction. a. HBr (aq) + Mg (s) H (g) + MgBr (aq) b. 3 KOH (aq) + H 3 PO 4 (aq) 3 H O (l) + K 3 PO 4 (aq) c. NaOH (aq) + Al (s) NR d. C 5 H 1 (l) + 8 O (g) 6 H O (g) + 5 CO (g) 10. Circle all the eamples below that are equal to 1 mole: 47.88 g tin 44.01 g carbon dioide.4 L Br (l) at STP 6.03 10 H O molecules.4 L O 3 (g) at STP 58.44 g sodium chloride -H + 11. Consider the following reaction: NH + 4 (aq) + HSO 3 (aq) H SO 3 (aq) + NH 3 (aq) Circle all that apply for each of the following: +H + a. NH + 4 (aq) is. an Arrhenius acid a Bronsted-Lowry acid an Arrhenius base a Bronsted-Lowry base b. HSO 3 (aq) is. an Arrhenius acid a Bronsted-Lowry acid an Arrhenius base a Bronsted-Lowry base CHM 130 Final Eam Practice Problems Key page 3 of 6
15. Calculate the number of hydrogen atoms in 5.0 g of urea, (NH ) CO. 3 mol (NH ) CO 6.010 (NH ) CO 4 H atoms 5.0 g (NH ) CO 60.07 g (NH ) CO 1 mol (NH ) CO (NH ) CO = 1.0010 4 H atoms 13. Consider the following reaction: Al (s) + 6 HCl (aq) AlCl 3 (aq) + 3 H (g) a. Calculate the volume of hydrogen gas produced when 5.00 g of aluminum reacts at STP. 5.00 g Al mol Al 6.98 g Al 3 mol H.4 L H mol Al mol H = 6.3 L H b. Calculate the volume of hydrogen gas produced when 15.00 g of hydrochloric acid reacts at STP. 15.00 g HCl mol HCl 36.46 g HCl 3 mol H.4 L H 6 mol HCl mol H CHM 130 Final Eam Practice Problems Key page 4 of 6 = 4.61 L H c. Identify the limiting reactant and the reactant in ecess when 5.00 g of aluminum reacts with 15.00 g of hydrochloric acid at STP. Since HCl produced the smaller amount of H gas, HCl is the limiting reactant, and Al is the reactant in ecess. 14. Consider the decomposition of sodium azide, NaN 3 : NaN 3 (s) spark Na (s) + 3 N (g) What is the percent yield if 50.0 g of sodium azide produced 9.7 g of nitrogen. 50.0 g NaN 3 mol NaN3 65.0 g NaN 3 3 mol N mol NaN 3 8.0 g N mol N = 3.3 g 9.7 g N % yield = 100% = 9.0% 3.3 g N 15. Identify the reactant oidized, the reactant reduced, the oidizing agent, and the reducing agent in each of the following redo reactions: Zn Zn + + e LEO 0 +1-1 +1-1 0 a. Zn(s) + HCl(aq) ZnCl (aq) + H (g) H + + e H GER Zn is oidized, acting as the reducing agent; HCl is reduced, acting as oidizing agent. C -4 C +4 + 4 e LEO -4 +1 0 +1 - +4 - b. CH 4 (s) + O (g) H O(g) + CO (g) O + 4 e 4 O - GER CH 4 is oidized, acting as the reducing agent; O is reduced, acting as oidizing agent. 3 H 6 H + + 6 e LEO 0 0-3 +1 c. N (g) + 3 H (g) NH 3 (g) N + 6 e N -3 GER H is oidized, acting as the reducing agent; N is reduced, acting as oidizing agent. N
Al Al +3 + 6 e LEO + -1 0 +3-1 d. 3 SnCl (aq) + Al (s) AlCl 3 (aq) + 3 Sn (s) 3 Sn + + 6 e 3 Sn GER Al is oidized, acting as the reducing agent; SnCl is reduced, acting as oidizing agent. 16. A 0.750 ml bubble at 4 C and 6.00 atm occupies what volume at.50 C and 75 mmhg? V P1 V1 T = T P (4560 mmhg) (0.750 ml) (96K) = (77K)(75 mmhg) = 1 5.05 ml 17. Which of the following that increase from left to right across the Periodic Table? Atomic radius, Ionization energy, Metallic character, Electronegativity, # of valence electrons Ionization energy, Electronegativity, # of valence electrons 18. Circle all of the following that increase from top to bottom down the Periodic Table? Atomic radius, Ionization energy, Metallic character, Electronegativity, # of valence electrons See net page for problem #19. Atomic radius, Metallic character 0. Consider the following si choices below: A. ionic bond D. dispersion (London) forces G. metallic bonds B. polar covalent bond E. dipole-dipole forces C. nonpolar covalent bond F. hydrogen bond Give the letter for the type of bond or intermolecular force described for each of the following: F i. The bonds broken when NH 3 (l) boils. B ii. The bonds holding atoms together in water. D iii. The bonds broken when a sample of Br (s) boils. C iv. The bonds holding the atoms together in a Cl molecule. A v. The bonds broken when a sample of KBr melts. E vi. The bonds holding broken when a sample of H S(l) boils. E vii. The bonds holding two HBr molecules together in a sample of HBr(l). B viii. The bonds holding atoms together in a sample of HF(l). G i. The bonds holding atoms together in a sample of Pb(s). 1. Which of the following does NOT increase with stronger intermolecular forces between molecules? a. boiling point b. molar heat of vaporization c. surface tension d. vapor pressure. Circle all of the following that will be soluble in or miscible with water: CH 3 Cl(l) C graphite (s) CO (s) K 3 PO 4 AgBr HCN(l) Ag(s) I (s) 3. Circle all of the following that will be soluble in or miscible with olive oil (a nonpolar solvent): CH 3 Cl(l) C graphite (s) CO (s) K 3 PO 4 AgBr HCN(l) Ag(s) I (s) CHM 130 Final Eam Practice Problems Key page 5 of 6