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Problem
BF3 reacts with F- to give BF4-, but AlF3 reacts with F- to give AlF63-. Explain.
Problem 1
Which of the following elements is the best conductor of electricity? (LO 22.1)
(a) N (b) As
(c) P (d) Bi
Problem 4
Which element will react most vigorously with water, and what is the reaction that occurs?
(a) Lithium; 2 Li(s) + 2 H2O(l) → 2 Li+(aq) + 2 H–(aq) + H2O2(aq)
(b) Potassium; 2 K(s) + 2 H2O(l) → 2 K+(aq) + 2 OH–(aq) + H2(g)
(c) Magnesium; Mg(s) + 2 H2O(l) → Mg2+(aq) + 2 OH–(aq) + H2(g)
(d) Barium; Ba(s) + 2 H2O(l) → Ba2+(aq) + 2 H–(aq) + H2O2(aq)
- Draw the electron-dot structure for BH3. What are the hybrid orbitals used by boron to form bonds with hydrogen, and will BH3 act as a Lewis acid or a Lewis base? (LO 22.9) (a) sp3; Lewis acid (b) sp3; Lewis base (c) sp2; Lewis acid (d) sp2; Lewis base
Problem 5
- The silicate anion in the mineral kinoite is represented by the following structure. The mineral also contains Ca2+ ions, Cu2+ ions, and water molecules in a 1:1:1 ratio. What are the formula and charge of the silicate anion, and what is the complete formula for the mineral? (LO 22.11)
Problem 6
(a) Si3O10^8-; Ca2Cu2Si3O10 · 2 H2O (b) Si3O8^10-; Ca3Cu2Si3O8 · 2 H2O (c) Si3O4^4-; CaCuSi3O8 · H2O (d) Si3O12^12-; Ca3Cu3Si3O12 · 3 H2O - Write chemical equations for the reaction of potassium with the following substances, ensuring that the numbers and kinds of atoms are the same on both sides of the equations. If no reaction occurs, write N.R. (b) Br₂ (c) O₂
Problem 7
- Describe the shape of each of the following molecules or ions, and tell which hybrid orbitals are used by the central atom. (a) GeBr4 (b) CO2 (c) CO32- (d) SnCl3-
Problem 9
Problem 10
Consider the following oxoacids: HClO, HClO2, HClO3, and HClO4. In which oxoacid does chlorine have an oxidation state of +5? Which oxoacid is the strongest?
(LO 22.17)
(a) HClO has a Cl oxidation state of +5, and HClO4 is the strongest acid.
(b) HClO2 has a Cl oxidation state of +5, and HClO is the strongest acid.
(c) HClO3 has a Cl oxidation state of +5, and HClO4 is the strongest acid.
(d) HClO4 has a Cl oxidation state of +5, and HClO is the strongest acid.
- Predict the geometrical structure of each of the following molecules or ions: (a) NO2- (b) PH3 (c) PF5 (d) PCl4+.
Problem 11
- Write a balanced equation for the reaction of an excess of O2 with each of the following elements: (b) P, (c) Al, (d) Si.
Problem 12
- Write a balanced net ionic equation for the reaction of each of the following oxides with water: (b) K2O, (c) SO3.
Problem 13
- Write electron-dot structures for each of the following molecules, and use VSEPR theory to predict the structure of each: (a) H2S (b) SO2 (c) SO3.
Problem 14
- Write the formula for each of the following compounds, and indicate the oxidation state of the halogen: (a) Bromic acid (b) Hypoiodous acid.
Problem 15
- Give one example from main-group chemistry that illustrates each of the following descriptions. (a) Covalent network solid (b) Disproportionation reaction (c) Paramagnetic oxide (d) Lewis acid (e) Amphoteric oxide (f) Semiconductor (g) Strong oxidizing agent (h) Allotropes
Problem 16
Problem 20a
Look at the location of elements A, B, C, and D in the following periodic table:
(a) Write the formula of the simplest binary hydride of each element.
Problem 20d
Look at the location of elements A, B, C, and D in the following periodic table:
(d) Which hydrides react with water to give an acidic solution, and which give a basic solution?
Problem 21
Look at the location of elements A, B, C, and D in the following
periodic table:
(c) Which hydrides react with water to give H2 gas? Write a balanced net ionic equation for each reaction.
Problem 22.100
Using the shorthand notation of Figure 22.9, draw the structure of the cyclic silicate anion in which four SiO4 tetrahedra share O atoms to form an eight-membered ring of alternating Si and O atoms. Give the formula and charge of the anion.
Problem 22.9
Which of the following oxides will be more soluble in acidic solution? (LO 22.14)
(a) SiO2 (b) NO2
(c) BaO (d) B2O3
Problem 22.96
Why are CO and CN– so toxic to humans?
Problem 22.3
Which of the following elements (X) will form a covalent hydride with the formula XH3 that is a gas at room temperature? (LO 22.4)
(a) Al (b) As (c) Ba (d) Se
Problem 22.47
GeCl4 reacts with Cl- to give GeCl62-, but CCl4 does not react with excess Cl-. Explain.
Problem 22.85
Explain why the properties of boron differ so markedly from the properties of the other group 3A elements.
Problem 22.101
Suggest a plausible structure for the silicate anion in the mineral thortveitite, Sc2Si2O7.
Problem 22.126
Arrange the following oxides in order of increasing basic character: Al2O3, Cs2O, K2O, N2O5.
Problem 22.113
Compare and contrast the properties of ammonia and phosphine.
Problem 22.99
Using the shorthand notation of Figure 22.9, draw the structure of the silicate anion in:
(a) K4SiO4 (b) Ag10Si4O13
What is the relationship between the charge on the anion and the number of terminal O atoms?
Problem 22.119
In what forms is oxygen commonly found in nature?
Problem 22.92
Draw the electron-dot structure for CO, CO2, and CO32–, and predict which substance will have the strongest carbon–oxygen bond.
Problem 22.94
Which of the group 4A elements have allotropes with the diamond structure? Which have metallic allotropes? How does the variation in the structure of the group 4A elements illustrate how metallic character varies down a periodic group?