January 2008 Chemistry Regents #11-20
Highlight to reveal answers and explanations
Questions 1-10 Questions 11-20 Questions 21-30 Questions 31-40 Questions 41-50 |
Questions | Answer | Explanations |
| 11 A solid substance is an excellent conductor of electricity. The chemical bonds in this substance are most likely (1) ionic, because the valence electrons are shared between atoms (2) ionic, because the valence electrons are mobile (3) metallic, because the valence electrons are stationary (4) metallic, because the valence electrons are mobile | 4 | electricity="moving charge" metals have moving electrons |
| 12 Magnesium nitrate contains chemical bonds that are (1) covalent, only (2) ionic, only (3) both covalent and ionic (4) neither covalent nor ionic | 3 | Mg(NO3)2 contains both Ionic and Covalent Metal and 2 nonmetals |
| 13 Which substance can be broken down by a chemical change? (1) antimony (3) hexane (2) carbon (4) sulfur | 3 | definition of a compound |
| 14 Which barium salt is insoluble in water? (1) BaCO3 (3) Ba(ClO4)2 (2) BaCl2 (4) Ba(NO3)2 | 1 | Table F |
| 15 Which unit can be used to express solution concentration? (1) J/mol (3) mol/L (2) L/mol (4) mol/s | 3 | Table T=Molarity |
| 16 Under which conditions of temperature and pressure is a gas most soluble in water? (1) high temperature and low pressure (2) high temperature and high pressure (3) low temperature and low pressure (4) low temperature and high pressure | 4 | Table G, has slope down, low temperature High pressure
Think Soda |
| 17 Given the equation representing a system at equilibrium: H2O(s)<==>H2O(l) | 2 | at normal pressure ice melts at 0C |
| 18 In a redox reaction, the total number of electrons lost is (1) less than the total number of electrons gained (2) greater than the total number of electrons gained (3) equal to the total number of electrons gained (4) equal to the total number of protons gained | 3 | conservation of charge #electrons lost =# gained |
| 19 Which formula represents an alkene? (1) C2H6 (3) C4H10 (2) C3H6 (4) C5H12 | 2 | Table Q, general formula is CnH2n |
| 20 Which term refers to the difference between the potential energy of the products and the potential energy of the reactants for any chemical change? (1) heat of deposition (3) heat of reaction (2) heat of fusion (4) heat of vaporization | 3
| definition of heat of reaction |