Chapter 9

More documents

Recommendations

Info

$Math 095 Final Exam Review - Faculty.chemeketa.edu$

HEINS09-095-117v4.qxd 12/30/06 1:58 PM Page 116 - <strong>Chapter</strong> 9 - a 6.00 g NaHCO 3 b11002 = 60.0% NaHCO 10.00 g 3 a 4.00 g Na 2CO 3 b11002 = 40.0% Na 10.00 g 2 CO 3 54. The balanced equation is 2 KClO 3 ¡ 2 KCl + 3 O 2 12.82 g mixture - 9.45 g residue = 3.37 g O 2 lost by heating Because the O 2 lost came only from KClO 3 , we can use it to calculate the amount of KClO 3 in the mixture. The conversion is: g O 2 ¡ mol O 2 ¡ mol KClO 3 ¡ g KClO 3 13.37 g O 2 2a 1 mol 32.00 g ba2 mol KClO 3 ba 122.6 g b = 8.61 g KClO 3 mol O 2 mol 3 in the mixture a 8.61 g KClO 3 12.82 g sample b11002 = 67.2% KClO 3 55. The balanced equation is Al(OH) 3 (s) + 3 HCl(aq) ¡ AlCl 3 (aq) + 3 H 2 O(l) The conversion is: L HCl ¡ g HCl ¡ mol HCl ¡ mol Al(OH) 3 : g Al(OH) 3 a 2.5 L day g HCl ba3.0 ba 1 mol L 36.46 g b ¢ 1 mol Al1OH2 3 3 mol HCl ≤ a 78.00 g b = 5.3 g Al1OH2 mol 3 >day Now calculate the number of 400. mg tablets that can be made from 5.3 g Al(OH) 3 ¢ 5.3 g Al(OH) 3 1000 mg ≤ a ba 1 tablet day g 400. mg b = 13 tablets>day 56. 4 P + 5 O 2 ¡ P 4 O 10 P 4 O 10 + 6 H 2 O ¡ 4 H 3 PO 4 In the first reaction: 120.0 g P2a 1 mol b = 0.646 mol P 30.97 g 130.0 g O 2 2a 1 mol 32.00 g b = 0.938 mol O 2 0.646 mol P 3.44 mol P This is a ratio of = 0.938 mol O 2 5.00 mol O 2 Therefore, P is the limiting reactant and the P 4 O 10 produced is: - 116 -
HEINS09-095-117v4.qxd 12/30/06 1:58 PM Page 117 - <strong>Chapter</strong> 9 - 10.646 mol P2¢ 1 mol P 4O 10 4 mol P ≤ = 0.162 mol P 4O 10 In the second reaction: 115.0 g H 2 O2a 1 mol 18.02 g b = 0.832 mol H 2O H 2 O 0.832 mol 5.14 mol and we have 0.162 mol P 4 O 10 . The ratio of is = P 4 O 10 0.162 mol 1.00 mol Therefore, H 2 O is the limiting reactant and the H 3 PO 4 produced is: 10.832 mol H 2 O2¢ 4 mol H 3PO 4 6 mol H 2 O ≤ a 97.99 g b = 54.4 g H mol 3 PO 4 - 117 -
Page 1 and 2: HEINS09-095-117v4.qxd 12/30/06 1:58
Page 21: HEINS09-095-117v4.qxd 12/30/06 1:58

Chapter 9

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?