January 2016 Chemistry Regents #16-20
Highlight to reveal answers and explanations
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Questions | Answer | Links | Explanations |
| 16 Which list includes three forms of energy? (1) chemical, mechanical, electromagnetic (2) chemical, mechanical, temperature (3) thermal, pressure, electromagnetic (4) thermal, pressure, temperature | 1 | temperature, pressure are not forms of energy | |
| 17 At STP a 1-liter sample of Ne(g) and a 1-liter sample of Kr(g) have the same (1) mass (2) density (3) number of atoms (4) number of electrons | 3 | Avogadro's hypothesis. Usually molecules but since they are Nobel gases, atoms can be used instead. | |
| 18 A reaction will most likely occur if the colliding particles have the proper (1) mass, only (2) mass and volume (3) orientation, only (4) orientation and energy | 4 | orientation and energy...you need both or no reaction | |
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| 19 Which factors have the greatest effect on the rate of a chemical reaction between AgNO3(aq) and Cu(s)? (1) solution concentration and temperature (2) solution concentration and pressure (3) molar mass and temperature (4) molar mass and pressure | 1 | pressure requires a gas and there is none molar mass has ho effect | |
| 20 Which expression represents the heat of reaction for a chemical change in terms of potential energy, PE? (1) (PEproducts) + (PEreactants) (2) (PEproducts) - (PEreactants) (3) (PEproducts) × (PEreactants) (4) (PEproducts) -- (PEreactants) | 4 | (PEproducts) -- (PEreactants) just know it | |
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