Chem 106 Comp Exam 1 PRACTICE
| 1. | Air occupies space and has mass, therefore it is | |
| energy | ||
| dense | ||
| colored | ||
| matter |
| 2. | Which of the following represents a physical change in matter | |
| a substance solidifies at 443 | ||
| a substance produces a gas when heated | ||
| a substance burns when heated | ||
| a substance changes color when exposed to air |
| 3. | Which of the following terms correctly applies to a molecule of CO2 | |
| triatomic, heteroatomic | ||
| polyatomic, diatomic | ||
| triatomic, homoatomic | ||
| diatomic, heteroatomic |
| 4. | Which of the following would NOT be classified as a compound | |
| NaCl | ||
| Cl2 | ||
| CCl4 | ||
| no correct |
| 5. | A solution can NOT be classified as a | |
| heterogeneous mixture | ||
| homogeneous mixture | ||
| pure substance | ||
| more than one choice is correct |
| 6. | Your friend has a mass of 85,400 g. What is his mass in kg? | |
| 8540.0 | ||
| 854.00 | ||
| 85.400 | ||
| 8.5400 |
| 7. | What is the exponent on the 10 when 0.000241 is correctly written in scientific notation | |
| -5 | ||
| -4 | ||
| -3 | ||
| -2 |
| 8. | (6.15 x 1015) x (1.41 x 10-3) Do the calculation above and express the answer using correct scientific notation |
|
| 8.67 x 1018 | ||
| 8.67 x 1015 | ||
| 8.67 x 1012 | ||
| 8.67 x 1011 |
| 9. | Which number has the greatest number of significant figures | |
| 6.900+ | ||
| 0.000031 | ||
| 6.12 x 109 | ||
| 3.1 x 1023 |
| 10. | 6.02 + 5.119 + 0.04218Do the calculation above. How many significant figures are justified for the answer | |
| 3 | ||
| 4 | ||
| 5 | ||
| 7 |
| 11. | How many mL are in a 16.0 oz beverage (1000 mL = 33.824 oz) |
|
| 2.11 x 103 | ||
| 541 | ||
| 473 | ||
| 0.541 |
| 12. | An apple is about 64% water by weight. What would the DRY weight of a 350 g apple be? (Be careful). | |
| 224 g | ||
| 126 g | ||
| 22.4 g | ||
| 12.6 g |
| 13. | How many potassium (K) atoms are in one molecule of K2HPO4 | |
| 1 | ||
| 2 | ||
| 6.02 x 1023 | ||
| 2 x (6.02 x 1023) |
| 14. | Atoms are neutral. How can they have no charge | |
| equal numbers of protons and neutrons | ||
| equal numbers of protons and electrons | ||
| equal number of neutrons and electrons | ||
| more than one choice is correct |
| 15. | What is the reason U-238 is different from U-235 | |
| three more electrons | ||
| three more protons | ||
| three more neutrons | ||
| more than one choice is correct |
| 16. | How would an atom of carbon containing 8 neutrons be represented | |
| 126C | ||
| 86C | ||
| 128C | ||
| 146C |
| 17. | How many electrons would be found in an atom represented as 2914X | |
| 43 | ||
| 29 | ||
| 15 | ||
| 14 |
| 18. | The average relative mass of an ozone molecule is 48.0 u. An ozone molecule contains only oxygen atoms. What does the molecular weight indicate about the formula of the ozone molecule | |
| it contains a single oxygen atom | ||
| it contains two oxygen atoms | ||
| it contains three oxygen atoms | ||
| the data tell nothing about the formula of an ozone molecule |
| 19. | How many atoms are contained in a sample of Krypton, Kr, that weighs 8.38 g | |
| Avogadro’s number | ||
| one-tenth Avagadro’s number | ||
| one | ||
| one-tenth |
| 20. | What is the mass of 0.500 mol of O2? | |
| 32.0 g | ||
| 16.0 g | ||
| 8.0 g | ||
| 0.500 g |
| 21. | What is the mass of 0.300 mol of CaS | |
| 1.81 x 1023 g | ||
| 72.2 g | ||
| 21.6 g | ||
| 0.300 g |
| 22. | How many atoms of Mg are present in 12.8 g of Mg? | |
| 77.1 x 1023 | ||
| 0.527 | ||
| 7.71 x 1025 | ||
| 3.17 x 1023 |
| 23. | The symbol of the element in period 2, group IIIA is | |
| Mg | ||
| Be | ||
| Al | ||
| B |
| 24. | How many orbitals are located in a 3d subshell | |
| 1 | ||
| 3 | ||
| 5 | ||
| 10 |
| 25. | What is the maximum number of electrons that can occupy the second shell | |
| 2 | ||
| 6 | ||
| 8 | ||
| 10 |
| 26. | What is the maximum number of subshells that can be found in the fourth shell | |
| 1 | ||
| 2 | ||
| 3 | ||
| 4 |
| 27. | Which of the following has the same number of valence electrons as silicon (Si)? | |
| C | ||
| Al | ||
| Cl | ||
| no correct response |
| 28. | If there are 5 electrons in a 2p subshell, how many unpaired electrons will there be | |
| 0 | ||
| 1 | ||
| 2 | ||
| 3 |
| 29. | Which element has the electronic configuration of 1s22s22p63s1 | |
| F | ||
| Na | ||
| Sc | ||
| Li |
| 30. | Which of the following elements contain a 2p subshell completely filled with electrons? | |
| Ne | ||
| P | ||
| Co | ||
| more than one choice is correct |
| 31. | Up and down arrows can be used to represent the spin of electrons. According to the Pauli exclusion principle, which of the following represents two electrons simultaneously occupying the same orbital? | |
| up arrow, up arrow | ||
| down arrow, down arrow | ||
| up arrow, down arrow | ||
| more than one choice is correct |
| 32. | In which of the following elements does the distinguishing electron occupy a "d" subshell? | |
| Cr | ||
| O | ||
| Kr | ||
| Sr |
| 33. | Which of the following elements is classified as a representative metal | |
| element 30 | ||
| element 26 | ||
| element 38 | ||
| element 63 |
| 34. | Which of the following properties depends on the gravitational pull on an object? | |
| mass | ||
| weight | ||
| volume | ||
| more than one choice is correct |
| 35. | Express 0.0016 x 105 in correct scientific notation. | |
| 1.6 x 102 | ||
| 1.6 x 108 | ||
| 1600 | ||
| it is correct as it is |
| 36. | 1.89 x 10-5/6.02 x 1012 Complete the calculation above and express the answer in correct scientific notation. |
|
| 3.14 x 10-18 | ||
| 3.14 x 107 | ||
| 3.14 x 10-7 | ||
| 3.14 x 10-17 |
|
|
| 37. | Do the calculation above and give the answer using the correct number of significant figures. | |
| 74,953 | ||
| 74,950 | ||
| 74,000 | ||
| 7.5 x 103 |
| 38. | Which of the following has a charge of -1, a mass of 1 amu, and is found outside the nucleus? | |
| electron | ||
| proton | ||
| neutron | ||
| no correct response |
| 39. | An atom contains 36 neutrons and 34 protons. What is the correct representation for this atom? | |
| 70/34 Se | ||
| 70/36 Kr | ||
| 70/34 Yb | ||
| 70/36 Yb |
| 40. | Determine the molecular weight for Ca3(PO4)2 in amu. | |
| 87.05 | ||
| 135.05 | ||
| 215.21 | ||
| 310.18 |
| 41. | How many molecules of CaO are in 0.500 moles of CaO molecules? | |
| 2 | ||
| 1 | ||
| 3.01 x 1023 | ||
| 6.02 x 1023 |
| 42. | How many molecules of oxygen are contained in 0.500 moles of Na2CO3? | |
| 3 | ||
| 1.5 | ||
| 3.01 x 1023 | ||
| 9.03 x 1023 |
| 43. | Which of the following subshells can contain the largest number of electrons? | |
| 2s | ||
| 3d | ||
| 4p | ||
| 5s |
| 44. | What is the maximum number of orbitals that can occupy the third shell? | |
| 3 | ||
| 6 | ||
| 9 | ||
| 14 |
| 45. | Which of the following exhibits a violation of Hund's Rule, where the number in parenthesis indicates the number of electrons in that orbital? | |
| 1s(2), 2s(2), 2px(1), 2py(0), 2pz(0) | ||
| 1s(2), 2s(1), 2px(1), 2py(0), 2pz(0) | ||
| 1s(2), 2s(2), 2px(1), 2py(1), 2pz(1) | ||
| 1s(2), 2s(2), 2px(2), 2py(2), 2pz(2) |
| 46. | Which of the following elements would be a conductor of electricity and be a brittle solid? | |
| Al | ||
| S | ||
| Ag | ||
| Si |
Answers: