Unit 3.3 Test: Basic Chemistry

Transcription

1 Unit 3.3 Test: Basic Chemistry

2 1. A student placed 2 grams of baking soda in a balloon and 100 ml of vinegar in an Erlenmeyer flask. After stretching the opening of the balloon across the neck of the flask, the student raised it to dump the baking soda into the flask. He immediately observed foaming bubbles in the flask and the balloon began to expand. The student concluded that A. only a physical change was occurring B. the baking soda and vinegar were products of a chemical reaction C. the gas was oxygen D. the bubbles indicated a chemical change was occurring 2. In a comparison of metals to nonmetals in the same period, metals tend to F. have more valence electrons G. have higher atomic numbers H. be less reactive J. have a lower atomic mass 3. 2Mg + O 2 2MgO In the equation above, what is the subscript of the oxygen molecule? A. 2 B. 0 C. 1 D In a physical change, it is true that A. The substances undergo a chemical reaction B. The substance does not change into a different substance C. The substance will expand as gas bubbles are produced D. The substances will always undergo an exothermic reaction 5. How many atoms of oxygen are in a molecule of glucose (C 6 H 12 O 6 )? Record your answer and fill in the bubbles on your answer document. Be sure to use the correct place value.

3 6. Which of the atoms shown above will have the most similar properties to the atom shown below? F. I G. II H. III J. IV

4 7. Which best describes the difference between two isotopes of carbon? A. Different protons only. B. Different neutrons only. C. Different protons and mass. D. Different neutrons and mass. 11. Plants are amazing because they can make their own food! The process that explains this phenomenon is called photosynthesis. The equation provided depicts the reactants and products involved: 6CO 2 + 6H 2 O C 6 H 12 O 6 + 6O 2 8. How many neutrons are in a neutral cadmium-112 atom? How many atoms of Oxygen can be found in the reactants? 9. When describing the organization of the Periodic Table, it includes both groups and periods. An element in period 4, group 17 will have the following characteristics: A. It is classified as a metalloid gas. B. It can be classified as a nonmetal liquid. C. It can be classified as a metal gas. D. It is classified as a metal solid 10. Which number should replace the blank to balance the following equation? 2H 2 + 2Cl 2 HCl A. 6 B. 12 C. 18 D In an experiment combining two clear liquids, a white solid is produced. This solid is called a precipitate. The formation of a precipitate -- F. indicates a physical reaction occurred. G. indicates a chemical reaction occurred. H. indicates that something was wrong with the experiment. J. indicates that one of the liquids instantly froze. F. 1 G. 2 H. 3 J. 4

5 13. Identify the products in the following chemical reaction. 2NaOH + 2HCl 2NaCl 2 + 2H 2 0 A. 2 HCl B. 2 NaOH + 2 HCl C. 2 NaCl HCl D. 2 NaCl H Identify the coefficient in the following equation. 16. Which of the following is an example of a chemical change? F. combustion of wood G. boiling water H. melting steel J. crystallization of sugar 17. Examine the following equation. The number 4 in "4H 2 0" indicates that the reaction- 12Mg 2 (CO 2 Cl 3 ) 2 F. 2 G. 3 H. 6 J. 12 A. produces 4 atoms of hydrogen. B. produces 4 molecules of water. C. produces 4 atoms of water. D. reaction uses 4 atoms of water. 15. A teacher asks a student to write the chemical equation for photosynthesis. The student s response is shown below. The equation is not balanced correctly. Which of these is balanced correctly? 18. The chemical formula for aspirin is C 9 H 8 O 4. Which best describes the number of atoms of each element in the formula? F. 9 chlorine, 8 helium, 4 oxygen G. 9 carbon, 17 hydrogen, 21 oxygen H. 9 carbon, 8 hydrogen, 4 oxygen J. 9 chlorine, 8 helium, 21 oxygen A. B. C. D.

6 19. All chemical equations must be balanced. This means that the same number of atoms of each of the elements must be found in both the reactants and the products of the reaction. Which scientific law does this illustrate? A. Law of Conservation of Mass B. Law of Superposition C. Law of Conservation of Energy D. Law of Reflection 21. Which of the following equations follows the Law of Conservation of Mass? 22. A. 3H 2 O 3H 2 + 3O 2 B. C 2 H 4 + 3O 2 2CO 2 + 2H 2 O C. C + 4H 2 CH 4 D. 2Na + Cl NaCl 20. The above diagram is a model of a molecule of Methane. What is the formula for Methane? How many atoms of oxygen are in hydronium? F. 3 G. 2 H. 1 J In a chemical equation, it is true that- F. CH 8 G. C 8 H 4 H. CH 4 J. C 8 H 8 A. the same molecules must be on both sides of the equation B. there can be elements on the reactant side that are not on the product side C. an element or compound must be accompanied by a phase change D. the coefficients indicate the number of molecules of each reactant used and the number of molecules of each product made

7 24. A student is conducting an investigation to see how the amount of a mystery substance added to water will affect the temperature. The student measures out 250 ml of room temperature water into four beakers. The student then measures out four different amounts of the mystery substance (4g, 8g, 12g, 16g). Next the student adds the different amounts of mystery substance to each of the beakers and takes the new temperature of each one. 26. Refer to the above information and diagrams. What is the initial temperature of the water prior to adding the mystery substance to the beakers? F. 18 C G. 16 C H. 12 C J. 8 C 25. Refer to the information and diagrams shown above. When the student adds 16 grams of the mystery powder to the water, the temperature should become A. -14 C B. -8 C C. -4 C D. 4 C

8 26. The table above shows that the more carbon atoms a compound has, the higher the compound s boiling point. Based on the data in the table, a reasonable estimate of the boiling point of the next compound, C 7 H 16, is F. 70 C G. 99 C H. 120 C J. 142 C 27. The substances that are present before a chemical reaction occurs A/F. products 28. The substances that are produced from a chemical reaction B/G. reactants 29. A change in matter that only affects the appearance of the substance C/H. Physical change 30. A change in matter which results in a new and different substance being formed D/J. Chemical change

9