August 2015 Chemistry Regents #77-78

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Questions 1-5 Questions 6-10 Questions 11-15 Questions 16-20 Questions 21-25 Questions 26-30 Questions 31-35 Questions 36-40 Questions 41-45 Questions 46-50

Questions 51-54 Questions 55-57 Questions 58-59 Questions 60-61 Questions 62-65 Questions 66-68 Questions 69-72 Questions 73-74  Questions 75-76  Questions 77-78  Questions 79-80  Questions 81-82  Questions 83-85

 

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Question 77-78

 

  Base your answers to questions 77 and 78 on the information below and on your knowledge of chemistry.

In a laboratory investigation, a solution that contains 13.2 grams of Pb(NO3)2 reacts completely with a solution that contains 12.0 grams of NaI, producing 18.4 grams of PbI2 and an undetermined mass of a second product, NaNO3. This reaction is represented by the balanced equation below.

Pb(NO3)2 + 2NaI → PbI2 +  2NaNO3

77 Identify the compound produced that is insoluble in water. [1]

Answer-->PbI2 or  lead(II) iodide

78 Determine the mass of NaNO3 produced. [1]

Answer-->6.8 g

on to Questions 79-80

 

 

Questions 1-5 Questions 6-10 Questions 11-15 Questions 16-20 Questions 21-25 Questions 26-30 Questions 31-35 Questions 36-40 Questions 41-45 Questions 46-50

Questions 51-54 Questions 55-57 Questions 58-59 Questions 60-61 Questions 62-65 Questions 66-68 Questions 69-72 Questions 73-74  Questions 75-76  Questions 77-78  Questions 79-80  Questions 81-82  Questions 83-85

 

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