CHEM 121 FINAL EXAM 2025 Updated Questions and Answers Updated (2025 / 2026) (Verified Answers)- PORTAGE LEARNING

CHEM 121 FINAL EXAM


Question 1
You may find the following resources helpful:
Scientific Calculator (Links to an external site.)
Periodic Table
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Do the three conversions shown below, showing all work:
1. 328 K = ? oC


2. 76oC = ? oF

3. 135oF = ? K

1. 328K - 273 = 55 oC K → oC (make smaller) -273


2. 76oC x 1.8 + 32 = 168.8 oF o
C → oF (make larger) x 1.8 + 32


3. 135oF - 32 ÷ 1.8 = 57.2 + 273 = 330.2 K o
F → oC →K

Question 2
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Scientific Calculator (Links to an external site.)
Periodic Table
Equation Table


Classify each of the following 3 as
an element, compound, solution or heterogeneous mixture and explain
your answer.
1. Pepperoni Pizza

2. Potassium oxide

3. Phosphorus

, 1. Heterogeneous Mixture; Pepperoni Pizza - is not on periodic table
(not element) - no element names (not compound)appears as more
than one substance (dough, cheese, pepperoni) = Hetero Mix
2. Compound; Potassium oxide - is not on periodic table (not
element) - has two element names = Compound
3. Element; Phosphorus - is on periodic table = Element

Question 3
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Scientific Calculator (Links to an external site.)
Periodic Table
Equation Table


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. 1.20 moles of Al2(CO3)3

2. 1.04 moles of C8H6NO4Cl
1. Grams = Moles x molecular weight = 1.20 x 233.99 = 280.8 grams


2. Grams = Moles x molecular weight = 1.04 x 215.59 = 224.2 grams



Question 4
You may find the following resources helpful:
Scientific Calculator (Links to an external site.)
Periodic Table
Equation Table


Balance each of the following 3 equations by placing coefficients in front of
each substance.
C8H18 + O2 → CO2 + H2O