January 2015 Chemistry Regents #16-20
Highlight to reveal answers and explanations
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Questions | Answer | Links | Explanations |
| 16 Which two gases can not be broken down by chemical means? (1) CO and He (3) Xe and He (2) CO and NH3 (4) Xe and NH3 | 3 | link | Definition of a Compound |
| 17 Two substances in a mixture differ in density and particle size. These properties can be used to (1) separate the substances (2) chemically combine the substances (3) determine the freezing point of the mixture (4) predict the electrical conductivity of the mixture | 1 | link | Property differences are used to separate mixtures |
| 18 Which unit is used to express an amount of thermal energy? (1) gram (3) joule (2) mole (4) pascal | 3 | link | Table D has units and their classifications |
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| 19 Under which conditions of temperature and pressure does a real gas behave most like an ideal gas? (1) low temperature and low pressure (2) low temperature and high pressure (3) high temperature and low pressure (4) high temperature and high pressure | 3 | link | Ideal conditions are like Ideal vacations High Temp., Low Pressure |
| 20 According to the kinetic molecular theory for an ideal gas, all gas particles (1) are in random, constant, straight-line motion (2) are separated by very small distances relative to their sizes (3) have strong intermolecular forces (4) have collisions that decrease the total energy of the system | 1 | link | See link for 4 assumptions of an ideal gas |
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