UNIT 3 TEST #1 (REG. CHEM.) - WRITTEN PART

Part 1 - Fill in the following chart.

 Name Atomic # Mass # # of no # of e- # of p+ Symbol 1.) nitrogen - 14 7 14 7 7 7 14N 2.) zinc - 65 30 65 35 30 30 65Zn 3.) iron - 55 26 55 29 26 26 55Fe 4.) iodine - 126 53 126 73 53 53 126I 5.) titanium - 48 22 48 26 22 22 48Ti 6.) tungsten - 184 74 184 110 74 74 184W 7.) argon - 39 18 39 21 18 18 39Ar

Part 2 - Solve the following problems.  Show your work!  Don't forget SF's and units with your answer!
8.)  What is the mass of 4.329 moles of tin?    4.329 moles | 118.7 g = 513.9 grams
| 1 mole

9.) How many atoms are contained in 35.36 grams of potassium?    35.36 g | 1 mole = 0.9043 moles
| 39.1 g
0.9043 moles | 6.022 x 1023 atoms = 5.446 x 1023 atoms K
| 1 mole

10.)  What is the mass of 9.8 x 1023 molecules of CO2?
9.8 x 10
23 'cules CO2 | 1 mole                  = 1.6 moles CO2
| 6.022 x 1023 'cules
1.6 moles CO2 | 44.0 grams = 70. grams CO2
| 1 mole

11.)  Using the following data, calculate the average atomic mass of neon.  Round your answer to one place to the
right of the decimal point.

Neon - 20 has a percent abundance of 90.92 %.
Neon - 21 has a percent abundance of 0.257 %.
Neon - 22 has a percent abundance of 8.82 %.
20 x 0.9092 = 18.184
21 x 0.00257 = 0.05397
22 x 0.0882 = 1.9404
20.17837  ~  20.2 amu