Chemistry 3A, Fall 2008 Name

Chemistry 3A, Fall 2008 Name:

Final Exam Worksheet

Instructor: B. Williams

1. Write the electronic structure for the following elements:

a. Complete electron configuration for cobalt

b. Orbital (Box) diagram for oxide

c. Abbreviated electron configuration for barium

2. Complete the following table:

Name / Symbol / # Protons / # Neutrons / # Electrons
chromium / 24 / 28 / 24
bismuth / 83 / 126 / 83
sulfide / 16 / 15 / 18
Copper (I) ion / 29 / 34 / 28

3. Perform each of the following conversions in the table. Use standard scientific notation and the correct significant figures:

µg / mg / g / kg
9.65×106 / 9.65×103 / 9.65 / 9.65×10-3
4.7x10-12 / 4.7x10-15 / 4.7x10-18 / 4.7x10-21
1.5x106 / 1.5x103 / 1.5 / 1.5x10-3
6.77x1015 / 6.77x1012 / 6.77x109 / 6.77x106
1.7955×107 / 17,955 / 1.7955×101 / 1.7955×10-2

4. On the basis of the general solubility rules predict the products of the following reactions and balance the equation. NOTE FOR FULL CREDIT: If no reaction (precipitate) is likely to form, write “NO REACTION” in place of the products.

5. A 5.25 ´ 10-3 kg sample of water was heated from 279 K to 65.6 °C. What was the energy (heat) required to heat this sample of water?

6. A 3.27 gram sample of argon gas occupies a volume of 2.25 L at 0 ºC and 1 atm. What volume would a 32.01 g sample of argon gas occupy under the same temperature and pressure?

7. Given:

Calculate how many molecules of NO2 are required to produce 16 liters of oxygen at STP.

8. A 75.0 L gas cylinder contains 5.26 g of N2 and 4.50 g of O2. What is the total pressure in the gas cylinder at 24 ºC?

9. Express the following numbers in standard scientific notation.

a. 63,000,023

b. 312546 ´ 10-3

10. How many significant figures are presented in each of the following numbers?

a. 3,000,400 b. 0.0069000

11. Evaluate each of the following and express your answer in scientific notation (with the appropriate amount of significant figures).

12. Complete the following table.

Compound / # Valence Electrons / Lewis Structure / Molecular geometry / Bond Dipoles
(use arrows)
See file on line :
Chem 3A Worksheet Final KEY (Page 5) / (around C)
(around Be)
(around O)

13. Balance each molecular equation and classify each of them in as many ways as possible by placing an X in the boxes applicable to each reaction. (20 pts)

acid-base / combustion / decompo-sition / precipitation / synthesis / double replacement / single replacement
√

acid-base / combustion / decompo-sition / precipitation / synthesis / double replacement / single replacement
√ / √

14. Name the following compounds:

15. Write the formula for each of the following binary compounds:

g. iron (II) phosphate

h. nitrous acid

i. perchloric acid

j. chromium (III) sulfate

k. trisilicon tetranitride

l. sodium bromate

16. How would you prepare a 500. mL of a 2.50 M KCl solution?

· Calculate the moles of solute present (= 1.25 mol KCl)

· Calculate the mass (in grams) of solute in 1.25 mol KCl ( = 93.2 g)

· Weigh out 93.2 g KCl and dissolve solute into a final volume of 500 mL with water.

17. Calculate the molarity of a solution when 25.0 mL of 12.0 M HCl is diluted to a final volume of 500. mL

18. Calculate the number of grams of NaCl that must be added to 25.0 g of water to prepare a 4.75% (m/m) solution of NaCl.

19. Given:

A solution of 0.102 M LiOH is used to neutralize 8.0 mL of H2SO4. If 22.0 mL of LiOH is required to reach the endpoint, then what is the molarity of the H2SO4 solution?