chemistry 121 / chem 121 exam complete 100% scored practice solution
Exam Page 1
Show the calculation of the molecular weight for the following two compounds, reporting your
answer to 2 places after the decimal.
(NH4)2CO3
2(14.01) + 8(1.008) + (12.01) + 3(16.00) = 96.09
C8H6NO4Br
8(12.01) + 6(1.008) + (14.01) + 4(16.00) + 79.90 =260.04
Answer Key
Show the calculation of the molecular weight for the following two compounds, reporting your answer
to 2 places after the decimal.
(NH4)2CO3
2N + 8H + C + 3O = 96.09
C8H6NO4Br
8C + 6H + N + 4O + Br = 260.04
Exam Page 2
Show the calculation of the number of moles in the given amount of the following 2 substances.
Report your answer to 3 significant figures.
12.0 grams of (NH4)2CrO4
12..084 = 0.0789 moles
15.0 grams of C8H8NOI
15.0/261.054 = 0.0574 moles
Answer Key
This study source was downloaded by 100000849317663 from CourseHero.com on 07-09-2022 18:34:43 GMT -05:00
https://www.coursehero.com/file/49228874/Exam-2docx/
, Show the calculation of the number of moles in the given amount of the following 2 substances.
Report your answer to 3 significant figures.
12.0 grams of (NH4)2CrO4
Moles = grams / molecular weight = 12..08 = 0.0789 mole
15.0 grams of C8H8NOI
Moles = grams / molecular weight = 15..05 = 0.0575 mole
Exam Page 3
Show the calculation of the number of grams in the given amount of the following 2 substances.
Report your answer to 1 place after the decimal.
1.05 moles of (NH4)2CrO4
1.05 x 152.084 = 160.0grams
1.18 moles of C8H8NOI
1.18 x 261.054= 308.0grams
Answer Key
Show the calculation of the number of grams in the given amount of the following 2 substances.
Report your answer to 1 place after the decimal.
1.05 moles of (NH4)2CrO4
Grams = Moles x molecular weight = 1.05 x 152.08 = 159.7 grams
1.18 moles of C8H8NOI
Grams = Moles x molecular weight = 1.18 x 261.05 = 308.0 grams
Exam Page 4
This study source was downloaded by 100000849317663 from CourseHero.com on 07-09-2022 18:34:43 GMT -05:00
https://www.coursehero.com/file/49228874/Exam-2docx/
Exam Page 1
Show the calculation of the molecular weight for the following two compounds, reporting your
answer to 2 places after the decimal.
(NH4)2CO3
2(14.01) + 8(1.008) + (12.01) + 3(16.00) = 96.09
C8H6NO4Br
8(12.01) + 6(1.008) + (14.01) + 4(16.00) + 79.90 =260.04
Answer Key
Show the calculation of the molecular weight for the following two compounds, reporting your answer
to 2 places after the decimal.
(NH4)2CO3
2N + 8H + C + 3O = 96.09
C8H6NO4Br
8C + 6H + N + 4O + Br = 260.04
Exam Page 2
Show the calculation of the number of moles in the given amount of the following 2 substances.
Report your answer to 3 significant figures.
12.0 grams of (NH4)2CrO4
12..084 = 0.0789 moles
15.0 grams of C8H8NOI
15.0/261.054 = 0.0574 moles
Answer Key
This study source was downloaded by 100000849317663 from CourseHero.com on 07-09-2022 18:34:43 GMT -05:00
https://www.coursehero.com/file/49228874/Exam-2docx/
, Show the calculation of the number of moles in the given amount of the following 2 substances.
Report your answer to 3 significant figures.
12.0 grams of (NH4)2CrO4
Moles = grams / molecular weight = 12..08 = 0.0789 mole
15.0 grams of C8H8NOI
Moles = grams / molecular weight = 15..05 = 0.0575 mole
Exam Page 3
Show the calculation of the number of grams in the given amount of the following 2 substances.
Report your answer to 1 place after the decimal.
1.05 moles of (NH4)2CrO4
1.05 x 152.084 = 160.0grams
1.18 moles of C8H8NOI
1.18 x 261.054= 308.0grams
Answer Key
Show the calculation of the number of grams in the given amount of the following 2 substances.
Report your answer to 1 place after the decimal.
1.05 moles of (NH4)2CrO4
Grams = Moles x molecular weight = 1.05 x 152.08 = 159.7 grams
1.18 moles of C8H8NOI
Grams = Moles x molecular weight = 1.18 x 261.05 = 308.0 grams
Exam Page 4
This study source was downloaded by 100000849317663 from CourseHero.com on 07-09-2022 18:34:43 GMT -05:00
https://www.coursehero.com/file/49228874/Exam-2docx/
