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MCAT Chemistry

Subjects : mcat, science
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. Have three valance electrons. In certain instances - some elements will loose three electrons - but they will also share electrons with another element to attain stability.






2. A chemical reaction involving the transfer of one or more electrons from one reactant to another; also called oxidation - reduction reaction.






3. One - half of the distance between the center of identical atoms that are not bonded together. Since effective nuclear charge increases when moving from left to right each additional electron is pulled more strogly toward the nucleus.






4. The number of atoms in exactly 12 g of pure 12c and equal to 6.022 x 10^23 is called






5. An equilibrium expression used to measure weak - acid strength - given by the ratio of the product of the products' molar concentrations to the product of the reactants' molar concentrations - with each term raised to the power of its stoichiometric






6. Redox reaction - in which the same species is both oxidized and reduced.






7. A chemical reaction involving the transfer of one or more electrons from one reactant to another; also called oxidation - reduction reaction.






8. The process of decomposing a chemical compound by the passage of an electric current.






9. Expression of auto - ionization of water into H+ and OH- at a certain temperature - given by the product of the ions' molar concentrations. Denoted by Kw and equal to 10-






10. Where half of the acid is neutralized by the base on a titration curveAn acid dissociation constant - Ka - (also known as acidity constant - or acid - ionization constant) is a quantitative measure of the strength of an acid in solution. It is the eq






11. Attractions between molecules caused by the electron motion on one molecule affecting the electron motion on the other through electrical forces; these are the weakest interactions between molecules






12. A measured amount of a solution of unknown concentration is added to a known volume of a second solution until the reaction between them is just complete






13. No two electrons or protons or neutrons in a given system can be in states characterized by the same set of quantum numbers






14. Keq describes the ratio of product concentration to reactant concentration - with each raised to the power corresponding ot its coefficient ion in the balanced equation






15. The weight in grams of compound that can be substituted by 1 atom of Hydrogen. GEW = MW / # of acidic Hyrdogens






16. The amount of product that can be made in a chemical reaction based on the amount of limiting reactant






17. The intermolecular force in which a hydrogen atom that is bonded to a highly electronegative atom is attracted to an unshared pair of electrons of an electronegative atom in a nearby molecule






18. Side - to side parallel orbitals overlap to share electrons - the 2nd/3rd covalent bond between two atoms - cannot rotate and maintain the bond.






19. Contains nonmetals - 7 valence electrons in it's outermost energy level. Very reactive






20. The amount of energy that reactants must absorb before a chemical reaction will start; also called free energy of activation.






21. An emperimentally determined mathmatical expression showing the rate of a reaction as a function of the concentration of its reactants






22. The lowest allowable energy state of an atom






23. Region in a molecule where atomic orbitals overlap - resulting in either a stable low - energy bonding orbital or an unstable high - energy antibonding orbital.






24. A reaction where a compound does Not change its molecular structure.






25. Charge assigned to an atom in a molecule or polyatmic ion - calculated by (# valence electrons) - (# 1/2 bonding electrons) - (# nonbonding electrons). Molecules containing atoms with lower formal charges tend to be more stable than those with higher






26. Second quantum number - designated by the letter 'l.' This 'angular momentum' refers to the subshells within each principle quantum energy level. It can take on the value of an integer in the 0 to (n -1) range. The four subshellscorresponding to l=0






27. One - half the distance between the nuclei of two atoms of the same element when the atoms are joined






28. PH of a molecule at which it contains no net electric charge - isoelectric point.






29. Atoms react by gaining or losing electrons so as to acquire the stable electron structure of a noble gas - usually eight valence electrons






30. Acids defined as electron - pair acceptors and bases as electron - pair donors.






31. Alkaline Earth Metals - 2 valence electrons +2 ions - Magnesium Mg






32. A representation of a displacement reaction showing only the reactive species and omitting the spectator ions.






33. The center of the atom which contains the protons and neutrons; in cells - structure that contains the cell's genetic material (DNA) and controls the cell's activities






34. 5 different orbitals shaped like clover leaves and max electrons is 10






35. An acid that will completely dissociate in aqueous solution - like HCl - HI - HClO4 HBr.






36. A reaction in which atoms of one element take the place of atoms of another element in a compound






37. Numbers that specify the properties of atomic orbitals and of their electrons






38. The solubility of a gas in a liquid is directly proportional to the partial pressure of that gas on the surface of the liquid


39. The process by which a gas escapes from one container to another at lower pressure through a tiny hole in the container.






40. Rare earth element group (elements 58-71)






41. Set of spectral lines appearing in the UV region when a hydrogen atom undergoes a transition from energy levels n>1 to n=1.






42. Standard Temperature and Pressure. 273 Kelvin (0 Celsius) - 1 atmosphere (760 torr - 760 kPA).






43. When polar molecules orient themselves such that the positive region of one molecule is close to the negative region of another molecule.






44. A dynamic condition in which two opposing changes occur at equal rates in a closed system






45. Small discrete increments of energy.






46. A reaction in which two or more substances combine to form a single substance A+B>>>>>>>C






47. An atom - radical - or molecule that has gained or lost one or more electrons and has a negative or positive charge






48. Alkali metals: highly reactive - therefore always compounds. - 1 valence electron +1 ion - Hydrogen H? - Lithium Li? - Sodium Na? - Potassium K? - Rubidium Rb? - Cesium Cs?






49. The slowest elementary step which is the limit for the rate of the other steps






50. Tells you how much solute is present compared to the amount of solvent