June 2023 Chemistry Regents #1-5
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Questions |
Answer | Links |
Explanations |
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1. Which phrase describes the nucleus of any atom? 1. has an overall positive charge 2. has an overall negative charge 3.contains negative electrons 4. contains positive electrons |
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nucleus has protons (+) and neutrons (no charge) |
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| 2. Which two particles each have a mass of
approximately one atomic mass unit? 1. an electron and a proton 2. an electron and a positron 3.a neutron and a proton
4. a neutron and a positron |
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a neutron and a proton 1 u each electron and
positron about 1/2000th u |
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3. The wave-mechanical model of the atom describes the location of electrons 1. as loosely packed in the nucleus of the atom 2 as densely packed in the nucleus of the atom 3. in circular paths around the atom 4. in orbitals outside the nucleus |
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electron are found in orbitals outside the nucleus |
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4. When a ground state electron in an atom moves to an excited state, the electron 1. absorbs energy as it moves to a higher energy state 2. absorbs energy as it moves to a lower energy state 3. releases energy as it moves to a higher energy state 4. releases energy as it moves to a lower energy state |
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ground state is a the lower energy of an electron excited is higher energy put in (absorb) energy to get tot the excited state |
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| 5. Which statement describes a chemical property of
iron? 1. Iron is malleable. 2. Iron conducts electricity. 3. Iron reacts with nitric acid 4. Iron has a high melting point.
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Chemical properties...look for a reaction Physical
doesn't change what it is |
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