CHEM 103 FINAL EXAM

CHEM 103
FINAL EXAM
Question 1
Click this link to access the Periodic Table. This may be helpful throughout
the exam.


1. Convert 845.3 to exponential form and explain your answer.


2. Convert 3.21 x 10-5 to ordinary form and explain your answer.
1. Convert 845.3 = larger than 1 = positive exponent, move decimal 2 places
= 8.453 x 102


2. Convert 3.21 x 10-5 = negative exponent = smaller than 1, move decimal 5
places = 0.0000321


Question 2

, Click this link to access the Periodic Table. This may be helpful throughout
the exam.


Do the conversions shown below, showing all work:


1. 246oK = ? oC
2. 45oC = ? oF
3. 18oF = ? oK


1. 246oK - 273 = -27 oC o
K → oC (make smaller)
-273
2. 45oC x 1.8 + 32 = 113 oF o
C → oF (make larger) x
1.8 + 32
3. 18oF - 32 ÷ 1.8 = -7.8 + 273 = 265.2 oK o
F → oC → oK


Question 3
Click this link to access the Periodic Table. This may be helpful throughout
the exam.


Show the calculation of the number of moles in the given amount of the
following substances. Report your answer to 3 significant figures.


1. Moles = grams / molecular weight = 12..15 = 0.0908 mole


2. Moles = grams / molecular weight = 15..17 = 0.0837 mole


Question 4
Click this link to access the Periodic Table. This may be helpful throughout
the exam.


Show the calculation of the percent of each element present in the following
compounds. Report your answer to 2 places after the decimal.