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Quantities in Chemical Reactions (Part 1). or Stoichiometry. You’re a car maker now! . Here’s the balanced “equation” for making a car: 1 body + 4 wheels + 2 wipers 1 chem- mobile Try this:. 1 body + 4 wheels + 2 wipers 1 chem- mobile.
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Quantities in Chemical Reactions(Part 1) or Stoichiometry
You’re a car maker now! Here’s the balanced “equation” for making a car: 1 body + 4 wheels + 2 wipers 1 chem- mobile Try this:
1 body + 4 wheels + 2 wipers 1 chem- mobile How many chem-mobiles can you make from 35 bodies? 35. How many chem-mobiles can you make using 80 wheels? 20. How many chem-mobiles can you make using 98 wiper blades? 49.
What assumption(s) are you making? 1 body + 4 wheels + 2 wipers 1 chem-mobile For 98 wiper blades, we assume that we have at least _______ bodies. 49;and _______ wheels. 196. The “coefficients” in this “equation” are the equivalent of moles in a balanced chemical equation.
Let’s take this to chemistry . . . Li3N(s) + 3H2O(l) NH3(aq) + 3 LiOH(aq) How many mol of lithium nitride are required to prepare 6 mol LiOH? 2 mol Li3N. Assume sufficent H2O. How many mol of water are required to react with 0.5 mol Li3N? 1.5 mol H2O.
Look at ratios in this equation . . . Li3N(s) + 3H2O(l) NH3(aq) + 3 LiOH(aq)in terms of moles: 1 mol 3 mol 1 mol 3 mol in terms of mass: 34.8 g 54.1 g 17.0 g 71.9 g in terms of molecules: 6.02E23 18.06E23 6.02E23 18.06E23 formula units molecules molecules formula units
Li3N(s) + 3H2O(l) NH3(aq) + 3 LiOH(aq) What mass of NH3 is expected from the reaction of 100 g of Li3N with sufficient water?
Li3N(s) + 3H2O(l) NH3(aq) + 3 LiOH(aq) 1 mol Li3N : 1 mol NH3 100 g ↓(/34.82 g·mol-1) 2.87 mol (x 1/1) 2.87 mol ↓(x 17.0 g·mol-1) 48.8 g NH3 expected
What mass of LiOH is expected from the reaction of 100 g of Li3N with sufficient water? 1 mol Li3N : 3 mol LiOH 100 g ↓(/34.82 g·mol-1) 2.87 mol(x 3/1) 8.62 mol ↓(x23.95 g·mol-1) 206 g LiOH expected
If 78.3 g of water is allowed to react with excess lithium nitride, how many molecules of ammonia would be produced? 3 mol H2O : 1 mol NH3 78.3 g ↓(/18.02 g·mol-1) 4.35 mol(x 1/3) 1.45 mol ↓(x 6.02E23molec·mol-1) 8.73E23 molecules NH3 expected
Try this one: What volume of H2(g) at SATP can be obtained from the reaction of 8.54 g of Mg with sufficient HCl(aq)? Mg(s) + 2 HCl(aq) MgCl2(aq) + H2(g) 8.54 g ↓(/24.3 g·mol-1) 0.351 mol(x 1/1)0.351 mol H2 ↓[x24.8L·mol-1(SATP)] 8.70 L H2 @ SATP expected
Get busy on this here work before I hog-tie y’all: p 298 PP 1 – 10 (do a few) p 300 PP 11 – 18 (do odd #s) p 304 PP 21 – 30 (do odd #s) p 305 RQ 4 – 10 (do as many as needed) Quiz next class