January 2017 Chemistry Regents #56-57

Highlight to reveal answers and explanations

 

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

Question 51-53 Questions 54-55
 Questions 56-57 Questions 58-59 Questions 60-61 Questions 62-65  Questions 66-68  Questions 69-72  Questions 73-77 Questions 78-79 Questions 80-82 Questions 83-85  

 

 

 

 

 #56-57
  

A sample of calcium carbonate, CaCO3, has a mass of 42.2 grams. Calcium carbonate has a gram-formula mass of 100. g/mol.

56 Show a numerical setup for calculating the number of moles in the sample of CaCO3. [1]

HIGHLIGHT TO SEE THE ANSWER

42.2/100

57 Determine the percent composition by mass of oxygen in the CaCO3. [1]

HIGHLIGHT TO SEE THE ANSWER

48%

 

  

on to Questions 58-59

  

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

Question 51-53 Questions 54-55
 Questions 56-57 Questions 58-59 Questions 60-61 Questions 62-65  Questions 66-68  Questions 69-72  Questions 73-77 Questions 78-79 Questions 80-82 Questions 83-85