Chemistry Quiz Exam # 1 Key PDF

# Chemistry Quiz **Name:** **Date:** 09/9/2024 Please, PRINT YOUR NAME. Circle the best answer. NO CELL PHONES! 5 points for each question for a total of 200 points. ## Questions 1. Which of the following metric relationships is incorrect? * 1 microliter = 10^-6 liters * 1 g...

# Chemistry Quiz **Name:** **Date:** 09/9/2024 Please, PRINT YOUR NAME. Circle the best answer. NO CELL PHONES! 5 points for each question for a total of 200 points. ## Questions 1. Which of the following metric relationships is incorrect? * 1 microliter = 10^-6 liters * 1 gram = 10³ kilograms * 10³ milliliters = 1 liter * **1 gram = 10² centigrams ** * 10 decimeters = 1 meter 2. The distance of 54 km equals (1Km = 1,000 m) * 0.054 m * 0.54 m * 540 m * 5400 m * **5.4 x 10⁴ m** 3. The degree of agreement among several measurements of the same quantity is called It reflects the reproducibility of a given type of measurement. * accuracy * error * **precision** * significance * certainty 4. The agreement of a particular value with the true value is called * **accuracy** * error * precision * significance * certainty 5. A scientist obtains the number 0.045006700 on a calculator. If this number actually has four (4) significant figures, how should it be written? * 0.4567 * 0.4501 * 0.0450 * 0.04500 * **0.04501** 6. Express the number 0.000191 in scientific notation. * 191 x 10^-6 * 1.91 x 10² * **1.91 x 10^-4** * 1.91 x 10⁴ * 0.191 x 10^-3 7. The state of matter for an object that has a definite volume but not a definite shape is * solid state * **liquid state** * gaseous state * elemental state * mixed state 8. Express 165,000 in exponential notation. * 1.65000 x 10⁵ * **1.65 x 10⁵** * 1.6500 x 10^-5 * 1.65 x 10^-5 * 165 x 10³ 9. Express the number 0.0470 in scientific notation. * 470 × 10^-4 * 4.70 x 10² * 4.7 x 10^-2 * **4.70 × 10^-2** * 0.470 × 10^-1 10. TF Color changes always indicate a chemical change. * **True** * False 11. You are asked to determine the perimeter of the cover of your textbook. You measure the length as 33.16 cm and the width as 24.83 cm. How many significant figures should you report for the perimeter? * 1 * 2 * **3** * 4 * 5 12. Convert: - 46.9°C = °F. Use (T_oF = T_oC X (9°F / 5°C) + 32°F) * -84.4 °F * -116 °F * **-52.4 °F** * 116 °F * 226.1 °F 13. A metric unit for length is * gram * milliliter * yard * **kilometer** * pound 14. Which of the following is not a unit in the SI system? * ampere * candela * Kelvin * meter * **calorie** 15. The density of gasoline is 0.7025 g/mL at 20°C. When gasoline is added to water: * **It will float on top.** * It will sink to the bottom. * It will mix so, you can't see it. * The mixture will improve the running of the motor. * None of these things will happen. 16. TF All physical changes are accompanied by chemical changes. * True * **False** 17. The boiling of water is a * physical change because the water merely disappears * **physical change because the gaseous water is chemically the same as the liquid** * chemical change because heat is needed for the process to occur * chemical change because a gas (steam) is given off * chemical and physical damage 18. The state of matter for an object that has both definite volume and definite shape is * **solid state** * liquid state * gaseous state * elemental state * mixed state 19. Bromine exists naturally as a mixture of bromine (mass number = 79 and bromine (mass number = 81) isotopes. An atom of bromine (mass number = 79) contains * **35 protons, 44 neutrons, 35 electrons** * 34 protons and 35 electrons, only * 44 protons, 44 electrons, and 35 neutrons * 35 protons, 79 neutrons, and 35 electrons * 79 protons, 79 electrons, and 35 neutrons 20. Which of the following atomic symbols is incorrect? * ¹⁴C₆ * ³⁷Cl₁₇ * ³²P₁₅ * ³⁹K₁₉ * **¹⁴N₈** 21. The formula of water, H₂O, suggests: * There is twice as much mass of hydrogen as oxygen in each molecule. * **There are two hydrogen atoms and one oxygen atom per water molecule.** * There is twice as much mass of oxygen as hydrogen in each molecule. * There are two oxygen atoms and one hydrogen atom per water molecule. * None of these. 22. All of the following are true except: * Ions are formed by adding electrons to a neutral atom. * **Ions are formed by changing the number of protons in an atom's nucleus.** * Ions are formed by removing electrons from a neutral atom. * An ion has a positive or negative charge. * Metals tend to form positive ions. 23. Using the rules of significant figures, calculate the following: 4.0021-0.247 * 3.755 * 4 * 3.7551 * 3.76 * 3.8 24. How many significant figures are there in the number 0.04560700? * 4 * 5 * **7** * 8 * 9 25. How many significant figures are there in the number 0.0006313? * 7 * 3 * 8 * **4** * 0 26. The element rhenium (Re) exists as two stable isotopes and 18 unstable isotopes. Rhenium (mass number = 185) has in its nucleus * 75 protons, 75 neutrons * 75 protons, 130 neutrons * 130 protons, 75 neutrons * **75 protons, 110 neutrons** * not enough information 27. For which pair is the SI prefix not matched correctly with its meaning? * mega = 10⁶ * kilo = 1000 * **deci = 10** * nano = 10^-9 * centi = 0.01 28. By knowing the number of protons a neutral atom has, you should be able to determine * the number of neutrons in the neutral atom * **the number of electrons in the neutral atom** * the name of the atom * two of the above * none of the above 29. TF The number of neutrons in an atom is the same for all neutral atoms of that element. * True * **False** 30. ⁴⁰Ca²⁺₂₀ has * 20 protons, 20 neutrons, and 18 electrons * 22 protons, 20 neutrons, and 20 electrons * 20 protons, 22 neutrons, and 18 electrons * 22 protons, 18 neutrons, and 18 electrons * 20 protons, 20 neutrons, and 22 electrons 31. A species with 12 protons and 10 electrons is * Ne²⁺ * Ti²⁺ * **Mg²⁺** * Mg * Ne^2- 32. The numbers of protons, neutrons, and electrons in ³⁹K⁺₁₉ are: * 20 p, 19 n, 19 e * 20 p, 19 n, 20 e * 19 p, 20 n, 20 e * 19 p, 20 n, 19 e * 19 p, 20 n, 18 e 33. What is the mass of a 6.267-mol sample of sodium hydroxide (NaOH)? * 40.00 g * **250.7 g** * 150.4 g * 6.382 g * 0.1567 g 34. An ion is formed * By either adding or subtracting protons from the atom. * **By either adding or subtracting electrons from the atom.** * By either adding or subtracting neutrons from the atom. * All of the above are true. * Two of the above are true. 35. Which of the following are incorrectly paired? * Phosphorus, Pr **Palladium, Pd** * Platinum, Pt * Lead, Pb * Potassium, K 36. Which of the following are incorrectly paired? * Copper, Cu * Carbon, C * Cobalt, Co * Calcium, Ca * **Cesium, Ce** 37. Which of the following are incorrectly paired? * Antimony, Sb * Silicon, Si * Silver, Ag * Argon, Ar * **Astatine, As** 38. How many significant figures are there in the number 3.1400? * 1 * 2 * **3** * 4 * 5 39. How many moles of hydrogen chloride (HCl) are contained in a 52.6-g sample of this gas? * 0.693 mol * **1.44 mol** * 89.1 mol * 52.2 mol * 2.89 mol 40. TF The number of electrons in an atom is the same for all neutral atoms of that element. * **True** * False