CHEM133 Week 7 Midterm Exam Questions and Answers APU

1. Question: What is the volume, in cubic centimeters, of a brick that is 4.0 in × 2.7 in × 8.0 in? 2. Question: A sailor circumnavigated the earth and covered 4,264,000 meters. Express this number in standard scientific notation. 3. Question: The state of matter for an object that has both definite volume and definite shape is 4. Question: How many of the following numbers contain 3 significant figures? 5. Question: In the spring of 2008, gasoline cost £1.029 per Liter in London. On the same day, the exchange rate was $1 = £0.497. What was the price of London gasoline in dollars ($) per gallon? 6. Question: How many electrons are in the ion, P3-? 7. Question: Name the following compound: CuSO4 8. Question: Which of the following is the formula for hydroiodic acid? 9. Question: What is the chemical symbol for an atom that has 29 protons and 36 neutrons? 10. Question: Elements A and Q form two compounds, AQ and A2 Q3 . The mass ratio (mass Q)/(mass A) for AQ is 0.574. What is the mass ratio (mass Q)/(mass A) for A2 Q3 ? 11. Question: What volume of 18 M sulfuric acid must be used to prepare 1.80 L of 0.215 M H2 SO4 ? 12. Question: 1.00 mole of O2 contains the same number of molecules as 13. Question: What is the mass of 4 atom(s) of copper in grams? 14. Question: A sample of ammonia has a mass of 45.5 g. How many molecules are in this sample? 15. Question: For which compound does 0.256 mole weigh 12.8 g? 16. Question: What is the concentration of sodium ion in the final solution if 17.5 mL of a 0.1050 M Na2 CO3 solution is added to 46.0 mL of 0.1250 M NaCl? 17. Question: Which of the following compounds is an Arrhenius base in water? 18. Question: A 6.82 g sample of potassium chlorate was decomposed according to the following equation: 19. Question: Using the redox reaction below determine which element is oxidized and which is reduced. 20. Question: Balance the chemical equation given below, and determine the number of moles of iodine that reacts with 30.0 g of aluminum. 21. Question: What is the binding energy of an electron in a metal whose threshold frequency for photoelectrons is 2.50 x 1014 Hz? 22. Question: In Bohr's atomic theory, when an electron moves from one energy level to another energy level more distant from the nucleus: 23. Question: Calculate the energy, in joules, required to excite a hydrogen atom by causing an electronic transition from the n = 1 to the n = 4 principal energy level. 24. Question: What is the de Broglie wavelength of a 300 g object moving at a velocity of 50 m/s? 25. Question: Calculate the wavelength of a neutron that has a velocity of 250 cm/s. 26. Question: The speed needed to escape the pull of Earth’s gravity is 11.3 km/s. What is this speed in mi/hr? 27. Question: Perform the following calculations: 28. Question: Suppose you start with 1.000 g of an unknown copper compound and isolate 0.9794 g of metallic copper. What is be the formula weight of the compound if there is only one copper atom per unit formula? 29. Question: Lithium, is used in dry cells and storage batteries and in high temperature lubricants, it has two naturally occurring isotopes, 6Li and 7Li. Calculate the atomic mass of lithium. 30. Question: The percent composition of an unknown compound is 41.09% C, 5.53% H, 9.59 % N and 43.79% O. 31. Question: If 30.0 mL of 0.15 M Ba(OH)2 was needed to neutralize 50.0 mL of an H3 PO4 solution. What is the concentration of the original H3 PO4 solution? 32. Question: If 2.50 g of NH3 reacts with 2.85 g of O2 . 33. Question: If 48.0 g of iodine are reacted with an excess of phosphorus according to the following chemical equation: 34. Question: Calculate the energy required for the electronic transition from n = 3 to n = 5 in the hydrogen atom. 35. Question: Calculate the wavelength (in nm) for the electronic transition from n = 3 to n = 5 in the hydrogen atom.