36 problems
1PRACTICE PROBLEMTest
2PRACTICE PROBLEMOf the following compounds, (I) which ones exist as molecules, and (II) which ones manifest as extended structures spanning three dimensions?NaCl, CO2, SiO2, BF3
3PRACTICE PROBLEMConsider the substances CS, CS2, and CS32-–. Provide the Lewis structure for each substance and identify which will have the strongest carbon–sulfur bond.
4PRACTICE PROBLEMTrue or False: Oxygen is most commonly found in the hydrosphere as O2.
5PRACTICE PROBLEMDraw a structure of PH3 describe its molecular geometry
6PRACTICE PROBLEMWhich of the following structures of sulfur is composed of crown-shaped S8 rings at 25°C?
7PRACTICE PROBLEMExplain the following: OF6 does not form, but SF6 does.
8PRACTICE PROBLEMThe molecule SeO3 exhibits a trigonal planar geometry, while the ion SeO32– exhibits a trigonal pyramidal geometry. Explain why.
9PRACTICE PROBLEMWhich compound has more ionic character, As2O5 or Ga2O3?
10PRACTICE PROBLEMDetermine which element from Group 4A forms the strongest π bond.
11PRACTICE PROBLEMWhich compound, SiF4 or GeF4, has more ionic character?
12PRACTICE PROBLEMWhich substance, SF4 or SiF4, is more covalent?
13PRACTICE PROBLEMPredict which of the following elements will form the strongest π bonds.
14PRACTICE PROBLEMWhich of the following molecules is polar and contains a main-group element that violates the octet rule?
15PRACTICE PROBLEMIdentify whether the following statement is true or false. Every bond in dialane (Al2H6) is a three-center, two-electron bond.
16PRACTICE PROBLEMDraw a structure for GeH4. What is the molecular geometry of the structure?
17PRACTICE PROBLEMConsider the elements of group 6A. Identify the element that forms the strongest π bond.
18PRACTICE PROBLEMWhich element–S, Cl, Sn, or Ge –can be used as a semiconductor?
19PRACTICE PROBLEMConsider the elements belonging to group 5A. Which element is most likely to form strong π bonds?
20PRACTICE PROBLEMThe two most common allotropes of phosphorus are white and red phosphorus. Identify which allotrope is more reactive and explain your answer.
21PRACTICE PROBLEMWhich of the following statements is true about the properties of ammonia and phosphine?I. Ammonia is trigonal planar, while phosphine is trigonal pyramidal.II. Ammonia is a good proton acceptor, while phosphine is not.III. Ammonia cannot exhibit hydrogen bonds, while phosphine can.IV. At room temperature, both ammonia and phosphine are colorless gases.
22PRACTICE PROBLEMIdentify whether the following statement is true or false. Carbon is the most abundant element in the Earth's crust among group 4A elements.
23PRACTICE PROBLEMWhich element among group 6A elements is the most abundant in the human body?
24PRACTICE PROBLEMAs4 has an analogous structure to P4, which produces a significant bond strain. Would the strain be reduced if arsenic used hybridized orbitals instead of pure p orbitals for bonding? Explain your answer.
25PRACTICE PROBLEMWhich carbon compounds are toxic to humans in small amounts?i. CO2ii. COiii. CO32–iv. CN–
26PRACTICE PROBLEMAmong the Group 4A elements, only carbon has an allotrope with a diamond structure, while the rest have metallic allotropes. Is this statement true or false? If it is true, justify your answer. If otherwise, state the correct answer.
27PRACTICE PROBLEMWhich carbon allotrope is sp2-hybridized, one atom thick, and an exceptional conductor of electricity?
28PRACTICE PROBLEMWhat is the oxidation state of carbon in SrC2? Is SrC2 an ionic carbide?
29PRACTICE PROBLEMWhat is the tetrahedron-based shorthand notation for the silicate anion in Na9Si3O10?What is the relationship between the number of terminal O atoms and the charge of an anion?
30PRACTICE PROBLEMWhat is the tetrahedron-based shorthand notation for a cyclic silicate anion consisting of five SiO4 tetrahedra that form a ten-membered ring composed of alternating Si and O atoms? What are the charge and chemical formula of the anion?
31PRACTICE PROBLEMWhy does SiCl4 react with Cl﹣ to produce SiCl6, whereas CCl4 does not react with Cl﹣?
32PRACTICE PROBLEMConsider the following silicate anion:What are its formula and charge?
33PRACTICE PROBLEMWhat is the possible tetrahedron structure for the silicate anion in gadolinium pyrosilicate (Gd2Si2O7)?
34PRACTICE PROBLEMWhen zirconium reacts with bromine at 500°C, it produces a metal halide with a composition of 34.75% Zr by weight. It is a molecular compound and not ionic, as indicated by the halide's melting and boiling points, which are -20°C and 200°C, respectively. Upon interaction with magnesium, this metal halide gives rise to pure zirconium metal. Provide the balanced equation for this reaction.
35PRACTICE PROBLEMConsider the elements listed in the periodic table:The binary bromides formed by these elements in their highest oxidation state could have one of the following structures:Identify the nonbromine atom and molecular formula in each possible structure.
36PRACTICE PROBLEMConsider the elements listed in the periodic table:The following diagrams illustrate potential structures for the binary bromides of each element in their highest oxidation state:The bromide of carbon (C) and germanium (Ge) have similar structures, whereas the bromides of oxygen (O) and selenium (Se) have different structures. Explain.
