1. John makes a model representing the structure of an atom. Which model correctly labels the location of the electrons (e), protons (p), and neutrons (n) in an atom? 2. Which statement describes the number and location of protons, electrons, and neutrons in potassium, which has an atomic mass number of 39? 19 protons within the nucleus, 19 electrons outside the nucleus, and 20 neutrons within the nucleus 20 protons within the nucleus, 20 electrons within the nucleus, and 19 neutrons outside the nucleus 20 protons within the nucleus, 20 electrons outside the nucleus, and 19 neutrons within the nucleus 19 protons outside the nucleus, 19 electrons within the nucleus, and 20 neutrons outside the nucleus 3. An element has 17 electrons, 17 protons, and 18 neutrons. What is the name of this element? argon phosphorus chlorine sulfur 4. Which of these statements describes the mass of an electron when compared with another atomic particle? The mass of an electron is about equal to the mass of a proton. The mass of a neutron is about equal to the mass of an electron. The mass of an electron is about 2,000 times as great as the mass of a proton. The mass of a neutron is about 2,000 times as great as the mass of an electron. 5. The atomic structure of an element is illustrated below. Which element has this atomic structure? gallium phosphorus silicon sulfur
6. Linda is working on the structural representation of an isotope of carbon,, as a part of her project on isotopes. Which representation correctly identifies the structure of the isotope? 7. A helium atom has an atomic number of 2 and an atomic mass of 4 amu (atomic mass units). How many protons and neutrons does a helium atom have? 2 proton, 0 neutrons 4 protons, 0 neutrons 2 protons, 2 neutrons 4 protons, 2 neutrons 8. Which one of these statements is true about the structure of a neutral atom? The atom has more electrons than protons. Most of the mass of an atom is found in the nucleus. The atom is a solid sphere made up of different charges. Electrons are in stationary positions around the nucleus. 9. What happens if the number of protons and neutrons is changed in an atom? Changing the number of protons changes the isotope, and changing the number of neutrons changes the mass. Changing the number of protons changes the mass, and changing the number of neutrons changes the charge. Changing the number of protons changes the element, and changing the number of neutrons changes the isotope. Changing the number of protons changes the charge, and changing the number of neutrons changes the element. 10. What are atoms of the same element that differ in the number of neutrons are called? anions isotopes cations nuclei 11. How many protons does the isotope Cobalt-60 contain? 27 32 12. How many neutrons does the isotope Carbon-14 contain? 6 8 13. Which of these represents a pair of isotopes? 33 60 12 14
14. Jennifer is researching the nuclear composition of the two isotopes of uranium, and What is the number of electrons, protons, and neutrons of the two isotopes? X: e - = 92, p + = 92, n o = 143 & Y: e - = 92, p + =92, n o = 145 X: e - = 92, p + = 143, n o = 143 & Y: e - = 92, p + = 145, n o = 145 X: e - = 92, p + = 143, n o = 235 & Y: e - = 92, p + = 145, n o = 237 X: e - = 143, p + = 143, n o = 92 & Y: e - = 145, p + = 145, n o = 92 15. Which of the following elements forms an Anion with a charge of -2? Oxygen Fluorine 16. Which of the following elements forms a Cation with a charge of +2? Oxygen Fluorine Magnesium Potassium Magnesium Potassium 17. Why do elements form Ions? Elements form ions to become less stable and defy the octet rule. Elements form ions to become less stable and satisfy the octet rule. 18. Fluorine forms an Ion (anion) what happened to its valence electrons? It gave one electron away It picked up 1 electron It did not gain or lose electrons Elements form ions to become more stable and satisfy the octet rule. Elements form ions to become more stable and defy the octet rule. 19. An unidentified element has 12 protons and 10 electrons. What is this element? C +2 Mg +2 C -2 Mg -2
20. The diagram below shows an atom. Which of the following diagrams shows another isotope of the same element? 21. The Hydrogen isotopes shown in the diagram below differ from each other by the number of protons in nucleus. protons & neutrons in nucleus. electrons in energy level. neutrons in nucleus.
Unit 1 Quiz A Answer Key Physical Science Unit 1 Quiz A: Atomic Theory Name: KEY. 1. B 2. A 3. B 4. D 5. B 6. C 7. B 8. B 9. C 10. C 11. A 12. B 13. B 14. A 15. A 16. C 17. C 18. B 19. C 20. B 21. D Unit 1 Quiz A Answer Key Name:. 1.. 2.. 3.. 4.. 5.. 6.. 7.. 8.. 9.. 10.. 11.. 12.. 13.. 14.. 15.. 16.. 17.. 18.. 19.. 20.. 21.. Unit 1 Quiz A Answer Key Name:. 1.. 2.. 3.. 4.. 5.. 6.. 7.. 8.. 9.. 10.. 11.. 12.. 13.. 14.. 15.. 16.. 17.. 18.. 19.. 20.. 21..