Download Chemistry 1035 Test 1 - Prof. Patricia G. Amateis and more Exams Chemistry in PDF only on Docsity! Chemistry 1035 Test 1 September 17, 2007 THIS IS FORM A Name __________________________ 6.02 x 1023 entities/mol Choose the single best answer to each question. 1. Which of the following is a 4th period transition metal? 1. Ca 2. Ni 3. Rf 4. Mo 2. The density of nickel is 8.90 g/cm3. Expressed in units of ng/nm3, the density is 1. 8.90 x 10-24 ng/nm3 2. 8.90 x 10-18 nm/nm3 3. 8.90 x 10-12 ng/nm3 4. 8.90 nm/nm3 5. 890. nm/nm3 3. The density of mercury is 13.6 g/mL. How many pounds does 1.0 quart of mercury weigh? (1 lb = 453.6 g; 1.057 qt = 1.0 L) 1. 28 lb 2. 32 lb 3. 36 lb 4. 17 lb 4. Which of the measured numbers below has the greatest number of significant figures? 1. 0.3100 2. 0.00310 3. 310. 4. 3.1 x 10 4 5. 0.000310 5. What is the formula for the species that contains 18 electrons, 17 protons and 20 neutrons? 1. 35S2─ 2. 35Cl─ 3. 37Cl 4. 37Cl─ 5. 37Ar 6. Bromine has two common isotopes, 79Br and 81Br. Which of the following statements is true? 1. 81Br has two more electrons than 79Br 2. 79Br has 79 neutrons. 3. 81Br has two more protons than 79Br 4. 79Br has 35 electrons and 44 protons 5. 81Br has two more neutrons than 79Br 7. A +3 ion with 41 electrons and 57 neutrons would be an isotope of the element 1. Nb 2. La 3. Ru 4. Sr 8. The element oxygen consists of three naturally occurring isotopes: 16O, 17O, 18O. The atomic mass of oxygen is 16.0 amu. What can be implied about the relative abundances of these isotopes? 1. More than 50% of all oxygen atoms are 17O. 2. Almost all oxygen atoms are 18O. 3. The abundances of 17O and 18O are very small. 4. The isotopes all have about the same abundance, about 33%. 9. Which of the following chemical formulas is incorrectly written? 1. LiI 2. SrF2 3. NaS 4. K3P 10. What is the correct formula of barium nitrite? 1. Ba(NO2)2 2. Ba3N2 3. Ba(NO3)2 4. BaNO3 20. Which of the following samples contains the largest number of atoms? 1. 1g C 2. 1g Li 2. 1g F2 4. 1g Ca 21. Consider the following reaction: Al(s) + H2SO4(aq) → Al2(SO4)3(aq) + H2(g) What mass of H2SO4 is required to completely react with a 15.2 g sample of Al? 1. 22.8 g 2. 55.2 g 3. 82.8 g 4. 112 g 22. Consider the following reaction: 2 Al(s) + 3 Cl2(g) → 2 AlCl3(s) What mass of product is formed when 2.00 g of Al react with 2.00 g of Cl2? (Molar mass of AlCl3 = 133. g/mol) 1. 3.75 g 2. 9.85 g 3. 6.77 g 4. 2.50 g 23. What mass of KCl (74.6 g/mol) is contained in 556 mL of a 2.3 M KCl solution? 1. 1.3 g 2. 95 g 3. 170 g 4. 37 g 24. Calculate the mass of PbI2 formed when 35.5 mL of 0.554 M KI reacts with excess Pb(NO3)2 according to the equation 2 KI(aq) + Pb(NO3)2(aq) → PbI2(s) + 2 KNO3(aq) 1. 9.07 g 2. 49.3 g 3. 4.54 g 4. 17.9 g 25. When 10.1 g of Cr reacts with excess oxygen, 11.9 g of Cr2O3 is collected. What is the percent yield of Cr2O3? (Molar mass of Cr2O3 = 152 g/mol) 4 Cr(s) + 3 O2(g) → 2 Cr2O3(s) 1. 80.4% 2. 87.6% 3. 74.2% 4. 40.3% (Answers on next page) Answers: 1. 2 2. 3 3. 1 4. 1 5. 4 6. 5 7. 3 8. 3 9. 3 10. 1 11. 2 12. 3 13. 4 14. 2 15. 4 16. 1. 17. 1 18. 1 19. 1 20. 2 21. 3 22. 4 23. 2 24. 3 25. 1
