1 / 15

Tonight ’ s Homework

Tonight ’ s Homework. skim ch 11.2 (373 – 377) p 393, # 60 – 64, 67. Homework Review. 45. When tin(IV) oxide is heated with carbon in a process called smelting, the element tin can be extracted. SnO 2 (s) + 2C(s)  Sn(l) + 2CO(g)

ismael
Download Presentation

Tonight ’ s Homework

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. Tonight’s Homework • skim ch 11.2 (373 – 377) • p 393, # 60 – 64, 67

  2. Homework Review 45. When tin(IV) oxide is heated with carbon in a process called smelting, the element tin can be extracted. SnO2(s) + 2C(s)  Sn(l) + 2CO(g) Interpret the chemical equation in terms of particles, moles, and mass. Particles: 1 f.u. SnO2 + 2 atoms C  1 atom Sn + 2 molecules CO Moles: 1 mole SnO2 + 2 mole C  1 mole Sn + 2 mole CO Mass: 150.71 g SnO2 + 24.02 g C  118.71 g Sn + 56.02 g CO

  3. Homework Review 49. Solid silicon dioxide, often called silica, reacts with hydrofluoric acid (HF) solution to produce the gas silicon tetrafluoride and water. a. Write the balanced chemical equation for the reaction. SiO2 (s) + 4 HF (aq)  SiF4 (g) + 2 H2O (g) b. List three mole ratios, and explain how you would use them in stoichiometric calculations. You should have listed 12 mole ratios. They are useful to convert from moles of one substance to moles of another.

  4. Homework Review 50. Chrome The most important commercial ore of chromium is chromite (FeCr2O4). One of the steps in the process used to extract chromium is the reaction of chromite with coke (carbon) to produce ferrochrome (FeCr2). 2C(s) + FeCr2O4(s)  FeCr2 (s) + 2CO2 (g) What mole ratio would you use to convert from moles of chromite to moles of ferrochrome? 1 mole FeCr2 / 1 mole FeCr2O4

  5. Homework Review 53. Antacids Magnesium hydroxide is an ingredient in some antacids. Antacids react with excess hydrochloric acid in the stomach to relieve indigestion. a. Balance the reaction of Mg(OH)2 with HCl. Mg(OH)2 + 2HCl  MgCl2 + 2H2O b. Write the mole ratio that would be used to determine the number of moles of MgCl2 produced when HCl reacts with Mg(OH)2. 1 mol MgCl2 / 1 mol Mg(OH)2 OR 1 mol MgCl2 / 2 mol HCl

  6. Stoichiometric Calculations section 11.2

  7. Mass Production (an analogy ) • 2-L bottles of soda • 100,000 bottles per order • Best case scenario, how many liters of soda should be “batched” at a time? • 200,000 L

  8. Thinking like a chemist… • “Balanced Chemical Equation” • Mole Ratio • Conversion

  9. The basics of stoichiometric conversions… • Best Case Scenario = Balanced Chemical Eqn. • The mole ratio is the missing link between the best case scenario (balanced chemical equation in moles) and reality (in grams). • DETERMINE mole ration FROM THE BALANCED EQUATION • 3 types of conversions • mole to mole • mole to mass • mass to mass • Use molar mass (MM) to convert between moles and mass. For all of them, GO TO MOLES FIRST!

  10. 3 groups – 3 reactions • https://www.youtube.com/watch?v=oqMN3y8k9So • https://www.youtube.com/watch?v=Mx5JJWI2aaw • https://www.youtube.com/watch?v=x2BXuI52fOI

  11. 3 groups – 3 problems • Determine what type of conversion • mole to mole • mole to mass • mass to mass • Work through the problem to solve it. • Outline the steps to solve this type of problem. • Be prepared to teach it to your classmates.

  12. Summary – Determine given and unknown, then…

  13. Groups 1 & 2 • Potassium metal reacts vigorously with water to produce potassium hydroxide and hydrogen gas. If 0.0400 moles of potassium is used, how many moles of hydrogen gas is created?

  14. Groups 3 & 4 • Determine the mass of sodium chloride (NaCl) commonly called table salt, produced when 1.25 moles of chlorine gas (Cl2) reacts vigorously with excess sodium.

  15. Groups 5 & 6 • Gasohol is a mixture of gasoline and ethanol. Determine the mass of CO2 produced from the combustion of 100.0 g ethanol (C2H5OH).

More Related