Chapter 7 Homework

Homework 7.1

1. Write the correct formulae for the compounds formed between the following elements:

a) potassium and iodine
b) magnesium and chlorine
c) sodium and sulfur
d) aluminum and sulfur
e) aluminum and nitrogen

2. Give the correct name for the compounds indicated by the following formulae:

a) AgCl
b) ZnO
c) CaBr₂
d) SrF₂
e) BaO
f) CaCl₂

3. What are monatomic ions?

4. Using only the periodic table, write the symbol and charge of the ion most typically formed by each of the following elements:
a) K
b) Ca
c) S
d) Cl
e) Ba
f) Br

5. Write the correct formulae for the compounds formed between the following elements:
a) sodium and iodine
b) calcium and sulfur
c) zinc and chlorine
d) barium and fluorine
e) lithium and oxygen

6. Write the correct formulae and give the names of the compounds formed by the following ions:
a) Cr²⁺ and F^1-
b) Ni²⁺ and O^2-
c) Fe³⁺ and O^2-

Homework 7.2

^{1. Write the formula and give the name for the compounds formed between the following ions:}
a) Cu²⁺ and Br^1-
b) Fe²⁺ and O^2-
c) Pb²⁺ and Cl^1-
d) Hg²⁺ and S^2-
e) Sn²⁺ and F^1-
f) Fe³⁺ and O^2-

2. Give the names for the following compounds:
a) CuO
b) CoF₃
c) SnI₄
d) FeS

3. What is the significance of a chemical formula?

4. Name the following compounds using the Stock system:
a) NaI
b) MgS
c) CaO
d) K₂S
e) CuBr
f) FeCl₂

5. Write the correct formulae for the following compounds formed between the following elements:
a) sodium and iodine
b) calcium and sulfur
c) zinc and chlorine
d) barium and fluorine
e) lithium and oxygen

6. Give the correct name for each of the following:
a) KCl
b) CaBr₂
c) Li₂O
d) MgCl₂

7. Write the correct formulae and give the correct names for each of the following:
a) Cr²⁺ and F^1-
b) Ni²⁺ and O^2-
c) Fe³⁺ and O^2-

8. Give the correct chemical formula for each of the following:
a) sulfurous acid
b) chloric acid
c) hydrochloric acid
d) hypochlorous acid
e) perchloric acid
f) carbonic acid
g) acetic acid

9. Write the correct chemical formula for each of the following:
a) sodium fluoride
b) calcium oxide
c) potassium sulfide
d) magnesium chloride
e) aluminum bromide
f) lithium nitrate
g) iron (II) oxide

Homework 7.3

1. Write the correct chemical formula for each of the following:
a) sodium iodide
b) calcium chloride
c) potassium sulfide
d) lithium nitrate
e) copper(II) sulfate
f) sodium carbonate
g) calcium nitrite
h) potassium perchlorate

2. Give the correct chemical names for each of the following:
a) Ag₂O
b) Ca(OH)₂
c) KClO₃
d) NH₄OH
e) FeCrO₄
f) KClO

Homework 7.4

1. Name the following compounds:
a) SO3
b) ICl3
c) PBr5

2. Write the correct formula for each of the following:
a) carbon tetraiodide
b) phosphorus trichloride
c) dinitrogen trioxide

3. In naming and writing formulae for binary molecular compounds, what determines the order in which the component elements are written?

4. Correctly name the following molecular compounds using the Prefix system:
a) CO₂
b) CCl₄
c) PCl₅
d) SeF₆
e) As₂O₅

5. Name each of the compounds in number 5 above using the Stock system.

6. Write the correct formula for each of the following:
a) carbon tetrabromide
b) silicon dioixde
c) tetraphosphorus decoxide
d) diarsenic trisulfide

Homework 7.5

1. Distinguish between binary acids and oxyacids, and give two examples of each.

2. a) Define salt.
b) Give two examples of salts.

3. Correctly name each of the following acids:
a) HF
b) HBr
c) HNO₃
d) H₂SO₄
e) H₃PO₄

Homework 7.6

1. Assign oxidation numbers to each atom in the following compounds:
a) HCl
b) CF₄
c) PCl₃
d) SO₂
e) HNO₃
f) KH
g) P₄O₁₀
h) HClO₃
i) N₂O₅
j) GeCl₂

2. Assign oxidation numbers to each atom in the following compounds or ions:
a) HF
b) CI4
c) H2O
d) PI₃
e) CS₂
f) Na₂O₂
g) H₂CO₃
h) NO₂^1-
i) SO₄^2-
j) ClO₂^1-
k) IO₃^1-

3. Write the correct formula for each of the following:
a) phosphorus (III) iodide
b) sulfur (II) chloride
c) carbon (IV) sulfide
d) nitrogen (V) oxide

4. Name each of the following using the Stock system:
a) Co(NO₃)₂
b) FePO₄
c) Hg₂SO₄
d) Hg₃(PO₄)₂

5. Assign oxidation numbers to each atom in the following compounds:
a) HI
b) PBr3
c) GeS₂
d) KH
e) As₂O₅
f) H₃PO₄

6. Name each of the following compounds using the Stock system where appropriate:
a) MgI₂
b) NaF
c) CS₂
d) N₂O₄
e) SO₂
f) PBr₃
g) CaCl₂
h) AgI

^{Homework 7.7}

1. Name the following compounds using the Stock system:
a) CI₄
b) SO₃
c) As₂S₃
d) NCl₃

^{Homework 7.8}

_{1. Find the formula mass of each of the following:}
a) H₂SO₄
b) Ca(NO₃)₂
c) PO₄^3-
d) MgCl₂

^{Homework 7.9}

1. How many moles of atoms of each element are there in one mole of the following compounds?
a) Al₂S₃
b) NaNO₃
c) Ba(OH)₂

2. Find the molar mass of each of the compounds listed in question 1 above.

3. Determine both the formula mass and molar mass of ammonium carbonate, (NH₄)₂CO₃.

4. Determine the number of moles of each type of monatomic or polyatomic ion in one mole of the following compounds:
a) KNO₃
b) Na₂SO₄
c) Ca(OH)₂
d) (NH₄)₂SO₃
e) Ca₃(PO₄)₂
f) Al₂(CrO₄)₃

^{5. Determine the formula mass and molar mass of each of the following compounds:}
a) XeF₄
b) C₁₂H₂₄O₆
c) Hg₂I₂
d) CuCN

^{Homework 7.10}

_{1. How many moles are there in the following:}
a) 6.60 g (NH₄)₂SO₄
b) 4.5 g Ca(OH)₂

^{2. How many molecules are there in the following:}
a) 25.0 g H₂SO₄
b) 125 g C₁₂H₂₂O₁₁

3. What is the mass in grams of 6.25 mol of Cu(NO₃)₂?

4. How many moles of atoms of each element are there in one mole of (NH₄)₂CO₃?

5. What is the mass in grams of 3.25 mol Fe₂(SO₄)₃?

6. How many moles of molecules are there in 250 g of hydrogen nitrate, HNO₃?

7. How many molecules of aspirin, C₉H₈O₄, are there in 10.00 g tablet of aspirin?

8. Determine the formula mass of each of the following compounds:
a) C₆H₁₂O₆
b) Ca(CH₃COO)₂
c) NH₄¹⁺
d) ClO₃<sup>1-

Homework 7.11</sup>

1. Calculate the percentage composition of the following compounds:
a) PbCl₂
b) Ba(NO₃)<sub>2

2</sub>. Calculate the percentage composition of water in the compound ZnSO₄ . 7 H₂O
3. Magnesium hydroxide, Mg(OH)₂, is 54.87% oxygen by mass.
a) How many grams of oxygen are in 175 g of the compound?
b) How many moles of oxygen is this?

4. Calculate the percentage composition of (NH₄)₂CO₃.
5. Calculate the percentage composition of each of the following compounds:
a) NaCl
b) AgNO₃
c) Mg(OH)₂

^{Homework 7.12}

1. A compound is found to contain 63.52% iron and 36.48% sulfur. Find its empirical formula.

2. Find the empirical formula of a compound found to contain 26.56% potassium, 35.41% chromium, and the remainder oxygen.

3. Analysis of 20.0 g of a compound containing only calcium and bromine indicates that 4.00 g of calcium are present. What is the empirical formula of the compound formed?

4. A compound is found to contain 36.48% Na, 25.41% S, and 38.11% O. find its empirical formula.

5. Find the empirical formula of a compound that contain 53.70% iron and 46.30% sulfur.

6. Analysis of a compound indicates that it contains 1.04 g K, 0.70 g Cr, and 0.86 g O. Find its empirical formula.

7. Determine the empirical formula of a compound found to contain 52.11% carbon, 13.14% hydrogen, and 34.75% oxygen.

^{Homework 7.13}

1. Determine the molecular formula of a compound with an empirical formula of CH and a formula mass of 78.110 amu.

2. A sample of a compound with a formula mass of 34.00 amu is found to consist of 0.44 g H and 6.92 g O. Find its molecular formula.

3. If 4.04 g of N combine with 11.46 g of O to produce a compound with a formula mass of 108.0 amu, what is the molecular formula of this compound.

4. The molar mass of a compound is 92 g/mol. Analysis of a sample of the compound indicates that it contains 0.606 g N and 1.390 g O. Find it molecular formula.

5. What three types of information are needed in order to find an empirical formula from percentage composition data?

6. What is the molecular formula of the molecule that has an empirical formula of CH2O and a molar mass of 120.12 g/mol?

7. A compound with a formula mass of 42.08 amu is found to be 85.64% carbon and 14.36% hydrogen by mass. Find its molecular formula.