Test your basic knowledge |

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. In a closed system - when opposing changes are taking place at equal rates - the system is said to be in _____ _______.






2. For a cell at concentrations and conditions other than standard - a potential can be calculated using this equation.






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






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






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






6. If an inert gas is introduced into a reaction vessel containing other gases at equilibrium - it will cause an increase in the ______ _____ within the container - but the increase will not affect the position of equilibrium.


7. 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.






8. For most substances - when a hot concentrated solution is cooled - the excess solid ________. This is useful in purification of the solute.






9. Rays made up of electrons in basic electron charges.






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






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






12. 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.






13. In titration - this is the point at which a particular indicator changes color.






14. Another way the second law is stated is that in any spontaneous change - the amount of free energy available ______.






15. In titration - this point occurs when equal numbers of equivalents of acid and base have been reacted. The solution at this point is neutral because neither of the ions of the salt in solution undergoes hydrolysis.






16. A theory of the hydrogen atom stating that the electron can exist in only certain stable energy levels and that when the electronic state of the atom changes - it must absorb or emit exactly that amound of energy equal to the difference betweent he f






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






18. The pressure exerted by each gas in a mixture is called its _____ pressure.






19. 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.






20. The law stating that change in internal energy is equal to the difference between the energy supplied toi the system as heat and the energy removed from the system as work performed on the surroundings.






21. The vapor pressure of an aqueous solution is always lowered by the additon of more solute - which causes the boiling point to be raised.






22. A state function in which it is the heat content of a substance.






23. The molecules in a gas are in constant - continueous - random - and straight-line motion.






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






25. 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






26. **Five factors that affect reaction rates: 1. The nature of the reactants and products. 2. The surface area exposed. 3. The concentrations. 4. The temperature. 5. The catalyst.






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


28. 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.






29. *The electrons found in the outermost shell are called _____ electrons. When these electrons are lost or partially lost through sharing - the oxidation state is assigned a positive value for the element. If valence electrons are gained or partially g






30. 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.


31. A law that states that under conditions of constant temperature and pressure - equal volumes of different gases contain equal numbers of molecules.






32. Liquids with strong attractive forces have ______ boiling points.






33. _____ bonds are present in molecules containing double or triple bonds.






34. *The nature of the reactants and products affect chemical reactions because some elements and compounds have bonds that when broken/formed - react more rapidly with each other than others.






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






36. The energy required to remove an electron from an isolated atom in its ground state.






37. The action of salts of weak acids or bases with water to form acidic or basic solutions.






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






39. A principle stating that when a system at equilibrium is disturbed by the application of a stress (change in temperature - pressure - or concentration) it reacts to minimize the stress and attain a new equilibrium position.


40. The amount of heat energy required to raise the temperature 1g of a substance by 1 degree celcius.






41. *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.






42. A chemical reaction formed from the breakdown of a compound into its individual elements or compounds.






43. The pressure exerted by the gas molecules when they are in equilibrium with the liquid.






44. A law stating that at constant pressure - the volume of a given quantity of a gas varies directly with the temperature.






45. A catalyst affects a chemical reaction by lowering the _____ _____ for both the forward and the reverse reactions equally.






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






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






48. Metals have electronegativities less than ____






49. State ________ depend only on the present state of the substance and not on the path by which the present state was attained. Enthalpy - energy - Gibbs free energy - and entropy are examples.






50. 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).