January 2004 Regents #1-10
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Questions 1-10 Questions 11-20 Questions 21-30 Questions 31-40 Questions 41-50 |
Questions | Answer | Explanations |
| 1 A neutral atom contains 12 neutrons and 11 electrons. The number of protons in this atom is (1) 1 (3) 12 (2) 11 (4) 23 | 2 | atoms protons =electrons |
| 2 Isotopes of an element must have different (1) atomic numbers (2) mass numbers (3) numbers of protons (4) numbers of electrons | 2 | definition of an isotope |
| 3 Which element is a noble gas? (1) krypton (3) antimony (2) chlorine (4) manganese | 1 | group 18 |
| 4 On the present Periodic Table of the Elements, the elements are arranged according to increasing (1) number of oxidation states (2) number of neutrons (3) atomic mass (4) atomic number | 4 | atomic number, look at it |
| 5 What is a property of most metals? (1) They tend to gain electrons easily when bonding. (2) They tend to lose electrons easily when bonding. (3) They are poor conductors of heat. (4) They are poor conductors of electricity. | 2 | metals lose electrons and become positive ions (low ionization energies) |
| 6 What is the correct formula for iron (III) phosphate? (1) FeP (3) FePO4 (2) Fe3P2 (4) Fe3(PO4)2 | 3 | Fe3+ PO43- --> FePO4 |
| 7 The bond between Br atoms in a Br2 molecule is (1) ionic and is formed by the sharing of two valence electrons (2) ionic and is formed by the transfer of two valence electrons (3) covalent and is formed by the sharing of two valence electrons (4) covalent and is formed by the transfer of two valence electrons | 3 | 2 non metal atoms covalent covalent share electrons |
| 8 The amount of energy required to remove the outermost electron from a gaseous atom in the ground state is known as (1) first ionization energy (2) activation energy (3) conductivity (4) electronegativity | 1 | definition |
| 9 What occurs when an atom of chlorine and an atom of hydrogen become a molecule of hydrogen chloride? (1) A chemical bond is broken and energy is released. (2) A chemical bond is broken and energy is absorbed. (3) A chemical bond is formed and energy is released. (4) A chemical bond is formed and energy is absorbed. | 3 | H + Cl --> H-Cl a bond is formed energy is released |
| 10 Which molecule is nonpolar? (1) H2O (3) CO (2) NH3 (4) CO2 | 4 | draw them O=C=O is symetrical |