QUIZ: ATOMS AND MOLECULES Name ___________________________________________ Date ________________ Period __________ QUIZ: ATOMS AND MOLECULES Directions: Please put your answers directly on this quiz. For multiple choice questions, write the letter of your choice on the line provided. For other questiosns, please use the space provided to make your response. Read each item carefully, and make sure that your response addresses what is being asked in the question. Do not leave any questions blank. Relax, good luck, and enjoy! 0. Do you have to use a silencer if you shoot a mime? 1. If an atom has 24 protons and 24 neutrons and a charge of -2, how many electrons does it have? 2. A polar molecule is one which A. has bears living at the north end. B. has local positive and negative charges, but no overall charge. C. would combine quickly and easily with olive oil. D. never contains nitrogen. _________ For questions 3-6, look at the large periodic table that Mr. Syracuse is holding. 3. How many protons does molybdenum (Mb) have? 4. What is the atomic mass (to the nearest a.u.) of molybdenum? 5. Does helium (He) have a full valence shell of electrons? 6. How many more electrons would oxygen need to have a full valence shell? 7. Look at the reaction shown below. Describe what is happening. You may write, draw, or both. glucose glucose maltose

8. What kind of bonds involve a sharing of electrons between two atoms? A. Hydrogen B. Covalent C. Ionic D. James _________ 9. If two substances are physically but not chemically combined, they form a A. Solution B. Isotope C. Suspension D. Mixture _________ 10. If Jean-Baptiste Lamarck added some sugar to his tea, the sugar is the ______ and the tea is the ______. A. atom; ion B. solvent; solute C. solute; solvent D. atom; molecule _________ 11. Why is it important that water floats when it freezes? 12. HCL, hydrochloric acid, is, as its name suggests, an acid. What would happen when you put HCL into solution in water? You may write, draw, or both. 13. Why is it important that the pH of your blood is maintained at about 7.4 by buffers? 14. What is being demonstrated in the picture below? 15. A trisaccharide such as raffinose contains how many monosaccharides? Draw raffinose below, using the as the symbol for a monosaccharide. F K H H O