January 2011 Chemistry Regents #1-10
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Questions | Answer | Explanations |
| 1 An orbital is a region of space where there is a high probability of finding (1) a proton (3) a neutron (2) a positron (4) an electron | 4 | electrons are found outside the nucleus in orbitals |
| 2 Which statement matches a subatomic particle with its charge? (1) A neutron has a negative charge. (2) A proton has a negative charge. (3) A neutron has no charge. (4) A proton has no charge. | 3 | protons + Neutrons= no charge electrons negative |
| 3 An atom of any element must contain (1) an equal number of protons and neutrons (2) an equal number of protons and electrons (3) more electrons than neutrons (4) more electrons than protons | 2 | atom=neutral Protons=electrons |
| 4 Which statement compares the masses of two subatomic particles? (1) The mass of an electron is greater than the mass of a proton. (2) The mass of an electron is greater than the mass of a neutron. (3) The mass of a proton is greater than the mass of an electron. (4) The mass of a proton is greater than the mass of a neutron. | 3 | protons=1amu neutrons=1amu electrons=1/1836 amu |
| 5 The bright-line spectrum of sodium is produced when energy is (1) absorbed as electrons move from higher to lower electron shells (2) absorbed as electrons move from lower to higher electron shells (3) released as electrons move from higher to lower electron shells (4) released as electrons move from lower to higher electron shells | 3 | spectra=excited electrons fall from higher to lower energy, releasing energy as light |
| 6 The valence electrons of a germanium atom in the ground state are located in the (1) first shell (3) third shell (2) second shell (4) fourth shell | 4 | Ge 2-8-18-4 <--outer level is valence |
| 7 The elements on the Periodic Table are arranged in order of increasing (1) atomic mass (2) atomic number (3) first ionization energy (4) selected oxidation state | 2 | atomic number |
| 8 Which list of elements contains a metal, a metalloid, a nonmetal, and a noble gas? (1) Be, Si, Cl, Kr (3) K, Fe, B, F (2) C, N, Ne, Ar (4) Na, Zn, As, Sb | 1 | metal=left side of staircase metalloid on the staircase nonmetal=right side of staircase noble gas group18 |
| 9 The two forms of oxygen, O2(g) and O3(g), have (1) different molecular structures and identical properties (2) different molecular structures and different properties (3) identical molecular structures and identical properties (4) identical molecular structures and different properties | 2 | different compounds have different properties and structures |
| 10 The sum of the atomic masses of the atoms in one molecule of C3H6Br2 is called the (1) formula mass (2) isotopic mass (3) percent abundance (4) percent composition | 1 | formula mass=mass of the formula |