January 2018 Chemistry Regents #1-5
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Questions | Answer | Links | Explanations |
1 Which statement describes the location of protons and neutrons in an atom of helium? (1) Protons and neutrons are in the nucleus. (2) Protons and neutrons are outside the nucleus. (3) Protons are outside the nucleus, and neutrons are in the nucleus. (4) Protons are in the nucleus, and neutrons are outside the nucleus. | 1 | Protons and neutrons are in the nucleus. | |
2 Given a list of atomic model descriptions: A: electron shells outside a central nucleus B: hard, indivisible sphere C: mostly empty space Which list of atomic model descriptions represents the order of historical development from the earliest to most recent? (1) A, B, C (3) B, C, A (2) A, C, B (4) B, A, C | 3 | hard, indivisible sphere then mostly empty space then electron shells outside a central nucleus | |
3 Which list represents the classification of the elements nitrogen, neon, magnesium, and silicon, respectively? (1) metal, metalloid, nonmetal, noble gas (2) nonmetal, noble gas, metal, metalloid (3) nonmetal, metalloid, noble gas, metal (4) noble gas, metal, metalloid, nonmetal | 2 | nonmetal, noble gas, metal, metalloid | |
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4 In the ground state, all atoms of Group 15 elements have the same number of (1) valence electrons (2) electron shells (3) neutrons (4) protons | 1 | valence electrons look at the last number in the electron configurations | |
5 What is the chemical formula for ammonium sulfide? (1) (NH4)2S (3) (NH4)2SO4 (2) (NH4)2SO3 (4) (NH4)2S2O3 | 1 | (NH4)2S | |
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