1 / 32

Chapter 15 Holt

Chapter 15 Holt . Chemical Reactions. Using Vocabulary. 1. Adding a(n) inhibitor will slow down a chemical reactions. 2. A chemical reaction that gives off light is called exothermic.

hastin
Download Presentation

Chapter 15 Holt

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Chapter 15 Holt Chemical Reactions

  2. Using Vocabulary • 1. Adding a(n) inhibitor will slow down a chemical reactions. • 2. A chemical reaction that gives off light is called exothermic.

  3. 3. A chemical reaction that forms one compound from two or more substances is called a synthesis reaction.

  4. 4. The 2 in the formula Ag2S is a subscript. • 5. The staring materials in a chemical reaction are reactants.

  5. Understanding Concepts • 6. Balancing a chemical equation so that the same number of atoms of each element is found in both the reactants and the products is an illustration of • C) the law of conservations of mass.

  6. 7. What is the correct chemical formula for calcium chloride? • B) CaCl2 • Ca has a valence of 2, so 2+ charge • Cl has a valence of 7, so -1 charge • So 2 Cl- with Ca++ makes CaCl2

  7. 8. In which type of reaction do ions in two compounds switch places? • D) double-replacement • Ex: NaOH + HCl --> NaCl + H2O

  8. 9. Which is an example of the use of activation energy? • C) holding a match to paper

  9. 10. Enzymes in your body act as catalysts. The role of enzymes is to • A) Increase the rate of chemical reactions (make the reactions happen faster)

  10. Short Answers • 11. Classify each of the following reactions: • A) Fe + O2 --> Fe2O3synthesis • Balanced this would be • 4Fe + 3O2 --> 2Fe2O3 • Iron + oxygen --> rust

  11. B) Al + CuSO4 --> Al2(SO4)3 + Cu • single replacement • Balanced this is • 2Al + 3CuSO4 --> Al2(SO4)3 + 3Cu • Aluminum + cupric sulfide --> aluminum sulfide plus copper

  12. C) Ba(CN)2 + H2SO4 --> BaSO4 +HCN • Double replacement • Balanced this is • Ba(CN)2 + H2SO4 --> BaSO4 + 2HCN

  13. 12. Name two ways that you could increase the rate of a chemical reaction. • 1) raise the temperature • ( this increases the concentration and/or the surface area) • 2) add a catalyst

  14. 13. The reactants are acetic acid (vinegar) and baking soda (sodium bicarbonate). • The products are carbon dioxide CO2 , water H2O, and sodium acetate.

  15. 14. Concept map is on the white board. • Terms are: • Chemical reaction • Chemical equation • Chemical formulas • Reactants, products, • Coefficients, subscripts

  16. Critical Thinking & Problem Solving • 15. Your friend is very worried by rumors he has heard about a substance called dihydrogen monoxide. What could you say to your friend to calm his fears? • Dihydrogen H2 • Monoxide O • So H2O - not to worry - its water !

  17. 16. As long as proper safety precautions have been taken, why can explosives be transported long distances without exploding? • Explosives need to absorb energy to being the reaction. Without this absorption, they can be transported safely.

  18. Math in Science • 17. Calculate the number of atoms of each element shown in each of the following: • A) CaSO4 • Ca - Calcium - 1 atom • S - Sulfur - 1 atom • O - Oxygen - 4 atoms

  19. B) 4NaOCl • Na - sodium - 4 atoms • O - oxygen - 4 atoms • Cl - chlorine - 4 atoms

  20. C) Fe(NO3)2 • Fe - iron - 1 atom • N - nitrogen - 2 atoms • O - oxygen - 6 atoms

  21. D) 2Al2(CO3)3 • Al - Aluminum - 4 atoms • C - carbon - 6 atoms • O - oxygen - 18 atoms

  22. 18. Write balanced equations for the following: • A) Fe + O2 --> Fe2O3

  23. 18. Write balanced equations for the following: • A) Fe + O2 --> Fe2O3 • Answer: • 4Fe + 3O2 --> 2 Fe2O3

  24. B) Al + CuSO4 --> Al2(SO4)3 + Cu • Answer

  25. B) Al + CuSO4 --> Al2(SO4)3 + Cu • Answer • 2Al + 3CuSO4 --> Al2(SO4)3 + 3Cu

  26. C) • Ba(CN)2 + H2SO4 --> BaSO4 + HCN

  27. C) • Ba(CN)2 + H2SO4 --> BaSO4 + HCN • Answer • Ba(CN)2 + H2SO4 --> BaSO4 + 2HCN

  28. 19) Balanced chemical equations: • A) bromine reacts with sodium iodide to form iodine and sodium bromide • Br2 + 2NaI --> I2 + 2NaBr

  29. B) Phosphorus reacts with oxygen gas to form diphosphorus pentoxide • 4P + 5O2 --> 2P2O5

  30. C) Lithium oxide decomposes to form lithium and oxygen • 2Li2O --> 4Li + O2

  31. Interpreting Graphics • 20. In the photo on page 393, what evidence supports that this is a chemical reaction? • Answer • - Bubbles of gas are produced • - Light is given off

  32. 21. Using the energy diagram on page 393, answer q’s a,b,c • A) “C” represents the energy of the products (far right section of graph) • B) “B” represents the activation energy of the reaction (increases then peaks) • C) Energy is “given off” by this reaction. • That’s the decline of energy below starting energy mark - “D” on the chart)

More Related