June 2018 Chemistry Regents #1-5
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Questions | Answer | Links | Explanations |
| 1 Which statement describes the charge and location of an electron in an atom? (1) An electron has a positive charge and is located outside the nucleus. (2) An electron has a positive charge and is located in the nucleus. (3) An electron has a negative charge and is located outside the nucleus. (4) An electron has a negative charge and is located in the nucleus. | 3 | electrons...negative...outside nucleus protons....positive...in nucleus | |
| 2 Which statement explains why a xenon atom is electrically neutral? (1) The atom has fewer neutrons than electrons. (2) The atom has more protons than electrons. (3) The atom has the same number of neutrons and electrons. (4) The atom has the same number of protons and electrons. | 4 | neutral...postive equals negative protons equal electrons | |
| 3 If two atoms are isotopes of the same element, the atoms must have (1) the same number of protons and the same number of neutrons (2) the same number of protons and a different number of neutrons (3) a different number of protons and the same number of neutrons (4) a different number of protons and a different number of neutrons | 2 | isotopes...same number protons different number of neutrons | |
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| 4 Which electrons in a calcium atom in the ground state have the greatest effect on the chemical properties of calcium? (1) the two electrons in the first shell (2) the two electrons in the fourth shell (3) the eight electrons in the second shell (4) the eight electrons in the third shell | 2 | valence electrons are the ones that determine chemical properties highest energy level electrons | |
| 5 The weighted average of the atomic masses of the naturally occurring isotopes of an element is the (1) atomic mass of the element (2) atomic number of the element (3) mass number of each isotope (4) formula mass of each isotope | 1 | definition of atomic mass | |
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