Chemistry 110 - 02
Winter 2017
Fifth Homework
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Study Hill and McCreary Chapter 4 sections 7, 8, 3 – 5, and 9 - 12.
Work on the Oxygen Content of Air lab report which is due February 2.
Complete the Molecular Models Lab. Be sure to staple your pre-lab to the back of your report.
It is due February 2, but please turn it in as soon as you are finished with it.
Learn the names and formulas for the polyatomic ions listed below.
The third quiz will include questions from the topics below. To be prepared for the quiz, you should be
able to answer these questions using only the periodic table you received in class and the information
given. Any quiz may include questions about lab safety and procedures.
Using the periodic table, be able to give the number of valence electrons of each element in Groups 1,
2, 13, 14, 15, 16, 17, and 18.
Using the periodic table, be able to give the electronegativity values of these elements: H, Li, Be, B, C,
N, O, F, and Cl (See Hill and McCreary Figure 4.5 on page 110.)
Using the periodic table, be able to give the symbol and name of the ion formed by each element in
Groups 1, 2, 16, and 17 (except Po) and by the elements aluminum, nitrogen, and phosphorus. (See
Figure 4.4)
Due 7:30 am Wednesday, February 1. 10 Points.
Late homework is not accepted after 8:30 am Thursday, February 2.
1. Properly record the answers to these operations involving measurements.
a. 58.0 mL × 0.89 g/mL =
b.7.68 g – 6.942 g =
2. Properly record the results of these calculations.
a. 6.359 g / 2.4200 mL =
b. 23.34 g – 22.867 g =
3. Perform these conversions. Show your work.
a. Convert 77.3 g to kg.
b. Convert 105.0 mL to L
c. Convert 0.8050 L to dL
d. Convert 8.43 m to cm.
e. Convert 364 mm to µm.
4. The density of zinc is 7.14 g/mL. What is the volume of 53.9 g of zinc? Show your
work.
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5. Give the name of an element that is a nonmetal, is extremely corrosive to tissue and
metals, forms compounds with hydrogen in a 1 to 1 atom ratio, and is usually found as
diatomic molecules as an element.
6. Which of these elements are in the same period as magnesium on the periodic table?
potassium, sodium, calcium, chlorine
7. Which of these elements are in the same family as nitrogen?
carbon, phosphorus, arsenic, fluorine
8. List the seven common elements that are usually found as diatomic molecules. (A diatomic
molecule is a molecule made of two atoms.)
9. For each pair of particles, tell whether they will attract, repel, or neither attract nor repel. Justify
your answer.
a. an electron and a proton
b. an electron and another electron
c. a proton and another proton
d. a neutron and an electron
10. Using the idea of electrical attractions and repulsions, explain why the electron in a hydrogen atom
does not fly away from the nucleus.
11. Read the section on isotopes in Hill and McCreary on pages 74 – 75. Then answer
these questions.
137
In March 2011, iodine-131 ( 131
53 I ) and cesium-137 ( 55 Cs ) were detected coming from
the earthquake damaged Fukushima Daiichi nuclear plant in Japan.
a. How many electrons, neutrons, and protons are in one atom of iodine-131?
b. How many electrons, neutrons, and protons are in one atom of cesium-137?
12. How many valence electrons does each of these atoms have?
a. calcium
b. carbon
c. chlorine
13. Answer Hill and McCreary Chapter 4 Problem 10 (on page 131).
14. Answer Hill and McCreary Chapter 4 Problem 11 (on page 131).
15. On page 110 of Hill and McCreary is a table of electronegativities (Figure 4.5). Atoms
with higher electronegativity pull on valence electrons more strongly than atoms with
lower electronegativity. Use the values in Figure 4.5 to identify which atom of each
pair pulls on valence electrons more strongly.
a. O or C
b. H or C
c. Br or F
d. N or O
16. What are the patterns of the electronegativity of elements on the periodic table? (In other words,
where on the periodic table are the elements with low electronegativity, where are the elements
with high electronegativity, etc.)
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17. According to Figure 4.5 on page 110 of Hill and McCreary, which five elements have the highest
electronegativity?
18. Using the concepts of electrical attractions and repulsions, explain why the atoms in a hydrogen
molecule stay together.
19. Draw the electron dot structure of each of these compounds.
a. CH4
b. C2H6
c. C3H8
20. Draw an electron dot structure for each of these molecules. Include all lone pairs.
a. HCl
b. H2CO
c. CF4
d. H2O
21. Draw an electron dot structure for each of these molecules. Include all lone pairs.
a. N2
b. CO2
c. C2H2
d. PH3
22. Draw an electron dot structure for each of these molecules. You may show bonding
pairs as dots or a line. Include all lone pairs. (There may be more than one possible
correct answer. Give just one.)
a. C3H8O
b. C2H4O
c. H2O2
d. C2H4Cl2
e. CH2Cl2
f. C2H7N
23. Predict which of these compounds has a stronger bond between the carbon atoms:
C2H6 or C2H2. Justify your answer.
24. For each of these bonds, indicate whether it is a polar bond or a nonpolar bond. If it is
a polar bond, show which atom has the little bit of positive charge and which atom has
a little bit of negative charge.
a. C – O
b. C – H
c. C – Cl
When hydrogen played oxygen,
And the game had just begun,
Hydrogen racked up two fast points,
But oxygen had none.
Then oxygen scored a single goal,
And thus it did remain.
Hydrogen 2 and oxygen 1,
Called off because of rain.
"When Hydrogen Played Oxygen
anonymous
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