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CLEP Chemistry 1

Subjects : clep, science, chemistry
Instructions:
  • Answer 50 questions in 15 minutes.
  • If you are not ready to take this test, you can study here.
  • Match each statement with the correct term.
  • Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.

This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.
1. When an electron moves from an excited state to the ground state - it _______ energy.






2. When the electron moves from the ground state to an excited state - it ______ energy.






3. Rays made up of positive electrodes in basic electron charges.






4. The _____ speed up the rate of a chemical reaction but do not change the equilibrium constant - it simply speeds up the rate of approach to equilibrium.






5. The temperature at which a substance's solid and liquid phases are in equilibrium.






6. Gases are composed of tiny - invisible molecules that are widely separated from one another in otherwise empty space.






7. The solubility of gases in liquid or solid solvents always increases with ________ pressure.






8. A valence theory that permits the geometric arrangement of atoms - or groups of atoms - about some central atom to be determined solely by considering the repulsions between the electron pairs present in the valence shell of the central atom.






9. Because of the low intermolecular forces - the melting points are low and evaporation takes place so easily that it may occur at room temperature.






10. A law stating that the vapor pressure of a solution at a particular temperature is equal to teh mole fraction of the solvent in the liquid phase multiplied by the vapor pressure of the pure solvent at the same temperature.






11. The ________ of an element is a number that measerures the relative strength in which the atoms of the element attract valence electrons in a chemical bond - on a scale of 0-4.






12. The change in enthalpy of an endothermic reaction is ________.






13. A catalyst lowers the ______ _____ _____ that must be overcome in order for the reaction to proceed. It merely speeds the approach to equilibrium but does not change Keq at all.


14. When a hydrogen atom is bonded to a highly electronegative atom - it will become partially _____-charged - and will be attracted to neighboring electron pairs. This creates a hydrogen bond. The more polar the molecule - the more effective the hydroge






15. Deviations from Boyles law that occur with real gases represent _______ behavior.






16. A chemical reaction formed from the union of its elements.






17. The maximum work derived from any change will be obtained only if the process is carried out in a reversible manner. All real - spontaneous changes are therefore not reversible - and the work that can be derived from an irreversible change is alway l






18. The relatively weak attractive forces between molecules that are apparent only when the molecules approach one another closely (usually at low temperatures and high pressure).






19. When a system at equilibrium is disturbed by adding or removing one of hte substances - all the concentrations will change until a new equilibrium point is reached with the same value of Keq.


20. **Proceeding across a period from left to right - the ionization energy _______.






21. Any spontaneous change in a chemical reaction will decrease the amount of free energy toward _______ as the process proceeds towards equilibrium.






22. Cells that convert electrical energy into chemical energy.






23. *The hypothetical ideal gas obeys exactly the mathematical statement of the ideal gas law. This statement is also called the _____ ___ ____ of an ideal gas because it relates the variables (P - V - n - T) that specify properties of the gas.






24. The most active metals are found in what corner of the periodic table?






25. The freezing point - boiling point - and vapor pressure of a solution differ from those of the pure solvent by amounts which are directly proportional to the molal concentration of the solute.






26. *Molecules of ideal gases have no attraction for one another and have no intrinsic volume - they are ______ _____






27. This law states that the total pressure exerted by a mixture of gases is equal to the sum of the partial pressures of the gases in mixture.






28. A chemical reaction where there is an actual exchange of partners to form new compounds. ex: AgNO3 + NaCl -> AgCl + NaNO3.






29. *The temperature affects chemical reactions with an increase of ___degrees C above room temperature - causing the reaction rate to double.






30. The ______ of the system is some particular set of conditions of pressure - temperature - number of moles of each component - and their physical form (ex: gas - liquid - solid or crystalline form).






31. A hypothetical gas would follow Boyles law under all conditions and is called?






32. In a closed system - when the rates of evaporation and condensation are equal - the system is in ____ ______.






33. In a _______ expansion of a gas - the opposing pressure is virtually equal to the pressure exerted by the gas. It is ______ because any slight increase in the external pressure will reverse the process and cause compression to occure.






34. The vapor pressure increases with increasing _____.






35. For a ________ reaction - the energy liberated in the exothermic reaction equals the energy absorbed in the endothermic reaction.






36. In an exothermic process - energy is released and ^E of reaction is ________.






37. The change in enthalpy of an exothermic reaction is ________.






38. The most active nonmetals are found in what corner of the periodic table?






39. Reactions that do not occur spontaneously can be forced to take place by supplying energy with an external current.






40. An increase in temperature causes the position of equilibrium of an exothermic reaction to be shifted to the _____ - while that of and endothermic reactions is shifted to the _______.


41. If this law was strictly obeyed - gases would not condense when they are cooled. This means that gases behave in an ideal fashion only at relatively high temperatures and low pressures.






42. When solids are heated at certain perssures - some solids vaporize directly without passing through the liquid phase.






43. The enthalpy changes associated with the reactions that correspond to the formation of a substance from its free elements are called?






44. The temperature at which the pressure of vapor escaping from the liquid equals atmospheric pressure.






45. Metals have electronegativities less than ____






46. When the rate of evaporation equals the rate of condensation - the system is in __________.






47. Increase in the concentrations of reactants shifts the equilibrium to the ______ - thus increasing the amount of products formed.


48. The process of determining the amount of a solution of known concentration that is required to react completely with a certain amount of a sample that is being analyzed.






49. For a solution in which a nonvolatile solute is dissolved in a solvent - the vapor pressure is due only to the vapor of the solvent above the solution. This vapor pressure is given by _______ law.


50. A law stating that at a constant temperature - the volume of a gas in inversely proportiona to the pressure.