Science

Q: In the mixed aluminum-boron hydride AlBH6, the number of hydrogen involved in 2c-2e bonds is ________, and the number of hydrogen involved in 3c-2e bonds is ________.

Q: The B-H-B bond in B2H6 is a three-________, two-________ bond.

Q: Elements in group 3A of the periodic table have the valence electron configuration ________.

Q: Elements in period 2 of the periodic table differ markedly from the heavier elements in the same group due to their especially small ________ and high ________.

Q: The number of metallic elements in period 3 of the periodic table is ________.

Q: Main-group elements are those elements in groups ________ through ________ of the periodic table.

Q: Which one of the following elements can form more than four chemical bonds with other elements? A) C B) N C) O D) As

Q: Which one of the following compounds exhibits the strongest hydrogen bonding between its molecules? A) CH3OH B) CH3F C) CH3Cl D) CH3Br

Q: Which one of the following compounds that contains a Group 6A element is least likely to exist? A) OF2 B) OF6 C) SF4 D) SF6

Q: Which one of the following elements forms the most acidic binary oxide? A) Cs B) Sn C) Se D) Te

Q: Which one of the following is not a main group element? A) Rb B) Sr C) U D) Pb

Q: Which of the following elements exhibits the most metallic character? A) In B) Sn C) Sb D) Te

Q: Which of the following elements forms the most ionic binary hydride? A) K B) Mg C) S D) Cl

Q: What is the most metallic element of group 3A? A) Al B) Ga C) In D) Tl

Q: The two-dimensional layer silicate ion shown in the picture below combines with magnesium and hydroxide ions to form talc. What is the formula and charge of the repeating unit of the silicate ion?A) SiO32-B) Si4O104-C) Si6O156-D) Si18O5028-

Q: The double-stranded silicate ion shown in the picture below combines with calcium and magnesium to form the mineral tremolite, which is a form of asbestos. What is the formula and charge of the repeating unit of the silicate ion? A) SiO32- B) Si4O116- C) Si6O1710- D) Si12O3012-

Q: The silicate ion shown in the picture below combines with beryllium and aluminum to form the mineral beryl. What is the formula and charge of the silicate ion? A) Si6O612+ B) Si6O122- C) Si6O1812- D) Si6O2424-

Q: What is the formula and charge of the silicate anion represented by the picture below? A) SiO22- B) SiO32- C) SiO44- D) Si4O128-

Q: The infinitely extended silicate ion shown in the picture below combines with calcium and magnesium to form the mineral diopside. What is the formula and charge of the repeating unit of the silicate ion? A) SiO32- B) Si2O64- C) Si3O108- D) Si6O2424-

Q: What is the formula and charge of the silicate anion represented by the picture below? A) SiO32- B) SiO44- C) Si2O63- D) Si2O76-

Q: The silicate ion shown in the picture below combines with zirconium to form the mineral zircon. What is the formula and charge of the silicate ion? A) SiO32- B) SiO44- C) Si4O104- D) Si4O116-

Q: Which oxoanion is the weakest base? A) oxoanion (1) B) oxoanion (2) C) oxoanion (3) D) oxoanion (4)

Q: Which oxoanion is the strongest base? A) oxoanion (1) B) oxoanion (2) C) oxoanion (3) D) oxoanion (4)

Q: Which oxoanion is the strongest acid? A) oxoanion (1) B) oxoanion (2) C) oxoanion (3) D) oxoanion (4)

Q: Which element indicated on the above periodic table forms a binary oxide with molecular structure (4) shown above? A) element A B) element B C) element C D) element D

Q: Which element indicated on the above periodic table forms a binary oxide with molecular structure (3) shown above? A) element A B) element B C) element C D) element D

Q: Which element indicated on the above periodic table forms a binary oxide with molecular structure (2) shown above? A) element A B) element B C) element C D) element D

Q: Which element indicated on the above periodic table forms a binary oxide with molecular structure (1) shown above? A) element A B) element B C) element C D) element D

Q: Which element indicated on the above periodic table forms a binary hydride with molecular structure (4) shown above? A) element A B) element B C) element C D) element D

Q: Which element indicated on the above periodic tableforms a binary hydride with molecular structure (3) shown above? A) element A B) element B C) element C D) element D

Q: Which element indicated on the above periodic table forms a binary hydride with molecular structure (2) shown above? A) element A B) element B C) element C D) element D

Q: Which element indicated on the above periodic table forms a binary hydride with molecular structure (1) shown above? A) element A B) element B C) element C D) element D

Q: What is the likely formula for the binary compound formed from the elements represented by letters B and C on the periodic table above? A) BC B) B3C C) BC3 D) B2C3

Q: What is the likely formula for the binary compound formed from the elements represented by letters B and D on the periodic table above? A) BD B) B3D C) BD3 D) B2D3

Q: What is the name for the group of elements indicated by the shaded portion of the periodic table? A) alkaline earth metals B) group 3A elements C) halogens D) noble gases

Q: At 25C the elements indicated by the shaded area in the following periodic table are all A) diatomic molecules. B) gases. C) liquids. D) nonmetals that are solids.

Q: At 25C the elements indicated by the shaded area in the following periodic table are all A) diatomic molecules. B) gases. C) liquids. D) solids.

Q: Which of the elements indicated on the above periodic table forms a common allotrope having molecular structure (3)? A) element A B) element B C) element C D) element D

Q: Which of the elements indicated on the above periodic table forms a common allotrope having molecular structure (2)? A) element A B) element B C) element C D) element D

Q: Which of the elements indicated on the above periodic table has a common allotrope stable at 25C having molecular structure (1)? A) element A B) element B C) element C D) element D

Q: Which of these molecules is most likely to contain good overlap of p orbitals, as shown in figure (a), rather than poor overlap of p orbitals, as shown in figure (b)?A) CO2B) SiO2C) GeO2D) SnO2

Q: What is the oxidation number of oxygen in BaO2? A) 0 B) -1/2 C) -1 D) -2

Q: What is the oxidation number of oxygen in KO2? A) 0 B) -1/2 C) -1 D) -2

Q: When KO2 is dissolved in water the evolution of oxygen takes place according to the reaction2 KO2(s) + H2O(l) -> O2(g) + 2 K+(aq) + HO2-(aq) + OH-(aq). In this reaction the O2- ion undergoesA) disproportionation.B) isomerization.C) only oxidation.D) only reduction.

Q: What is the reaction of potassium peroxide in water?A) 2 KO2(s) + H2O(l) -> O2(g) + 2 K+(aq) + HO2-(aq) + OH-(aq)B) K2O2(s) + H2O(l) -> 2 K+(aq) + HO2-(aq) + OH-(aq)C) 2 K2O2(s) + 2 H2O(l) -> 4 K+(aq) + 4 OH-(aq) + O2(g)D) K2O(s) + H2O(l) -> 2 K+(aq) + 2 OH-(aq)

Q: Which has the greatest number of unpaired electrons?A) O2-B) O2C) O2-D) O22-

Q: What is the bond length trend for molecular oxygen, the peroxide ion, and superoxide ion? A) O2 > O2- > O22- B) O2 > O22- > O2- C) O22- > O2- > O2 D) O22- > O2 > O2-

Q: Which of the following is a peroxide? A) Li2O B) K2O2 C) CaO D) CsO2

Q: What is the chemical formula for the superoxide ion? A) O- B) O2- C) O2- D) O22-

Q: When sodium metal is heated in excess oxygen it tends to form ________. A) an oxide B) a peroxide C) a superoxide D) an oxide and a superoxide

Q: Which reaction is not consistent with the chemistry of binary oxides?A) Na2O(s) + H2O(l) -> 2 Na+(aq) + 2 OH-(aq)B) SiO2(s) + 2 OH-(aq) -> SiO32-(aq) + H2O(l)C) Al2O3(s) + 6 H+(aq) -> 2 Al3+(aq) + 3 H2O(l)D) N2O5(aq) + 2 H+(aq) -> 2 NO2+(aq) + H2O(l)

Q: Which one of the following binary oxides is the most basic? A) B2O3 B) Al2O3 C) Ga2O3 D) In2O3

Q: Which one of the following binary oxides is the most basic? A) Na2O B) Al2O3 C) P2O5 D) SO3

Q: Which one of the following binary oxides is the most acidic? A) P2O5 B) As2O5 C) Bi2O5 D) Cl2O7

Q: Which one of the following binary oxides is the most acidic? A) Na2O B) Al2O3 C) P2O5 D) Cl2O7

Q: Which is classified as an amphoteric binary oxide? A) B2O3 B) CO2 C) Al2O3 D) SiO2

Q: Which is classified as an ionic binary oxide? A) MgO B) CO2 C) P2O5 D) SO3

Q: At 25C CO2 is a gas and SiO2 is a high-melting solid. In these compounds of oxygenA) both carbon in CO2 and silicon in SiO2 are -bonded to two oxygen atoms.B) both carbon in CO2 and silicon in SiO2 are -bonded to four oxygen atoms.C) carbon in CO2 is -bonded to two oxygen atoms and silicon in SiO2 is -bonded to four oxygen atoms.D) silicon in SiO2 is -bonded to two oxygen atoms and carbon in CO2 is -bonded to four oxygen atoms.

Q: What is not a good laboratory method for the preparation of oxygen?A) photosynthesis of sugars: 6 CO2(g) + 6 H2O(l) -> 6 O2(g) + 6H12O6(s)B) electrolysis of water: 2 H2O(l) -> 2 H2(g) + O2(g)C) catalytic decomposition of hydrogen peroxide: 2 H2O2(aq) -> 2 H2O(l) + O2(g)D) thermal decomposition of potassium chlorate: 2 KClO3(s) -> 2 KCl(s) + 3 O2(g)

Q: What is the total volume of hydrogen gas and oxygen gas that can be produced from the thermal decomposition of 0.340 grams of H2O2 at 700C and 755 mm Hg according to the chemical equation shown below?H2O2(l) -> H2(g) + O2(g)A) 402 mLB) 804 mLC) 1210 mLD) 1610 mL

Q: How many liters of oxygen gas can be produced at STP from the decomposition of 0.500 L of 3.00 M H2O2 according to the chemical equation shown below?2 H2O2(l) -> 2 H2O(l) + O2 (g)A) 16.8 LB) 22.4 LC) 33.6 LD) 67.2 L

Q: How many grams of KCl(s) are produced from the thermal decomposition of KClO3(s) which produces 25.0 mL of O2(g) at 25C and 1.00 atm pressure according to the chemical equation shown below?2 KClO3(s) -> 2 KCl(s) + 3 O2(g)A) 0.0508 gB) 0.0762 gC) 0.0835 gD) 0.152 g

Q: In the preparation of oxygen by the thermal decomposition of potassium chlorate shown below, what is the oxidation number change of the atom undergoing reduction?2 KClO3(s) -> 2 KCl(s) + 3 O2(g)A) - 8B) - 6C) + 1D) + 2

Q: Commercially oxygen is usually obtained by A) decomposition of mercury(II) oxide. B) decomposition of potassium chlorate. C) electrolytic decomposition of water. D) fractional distillation of air.

Q: Using the three different isotopes of oxygen 16O, 17O, 18O and the major isotope of hydrogen, 1H. Determine the number of different types of isotopically substituted hydrogen peroxide, H2O2, that could be formed. A) 3 B) 5 C) 6 D) 9

Q: There are three different isotopes of hydrogen 1H, 2H, 3H and three different isotopes of oxygen 16O, 17O, 18O. Indicate the number of different types of isotopically substituted water, H2O, that could be formed. A) 9 B) 12 C) 15 D) 18

Q: There are three isotopes of oxygen 16O, 17O and 18O. Indicate the number of different types of isotopically substituted diatomic oxygen. A) 3 B) 5 C) 6 D) 9

Q: Which is not true about elemental oxygen? A) Oxygen exists in two allotropic forms. B) Oxygen has a double bond. C) Oxygen is a diamagnetic element. D) Solid oxygen is pale blue in color

Q: How many liters of O2 gas at 25C and 1.00 atm pressure are needed to react with 120.5 grams of potassium hydride according to the chemical equation shown below?2 KH(s) + O2(g) -> H2O(g) + K2O(s)A) 18.4 LB) 36.7 LC) 73.5 LD) 147 L

Q: How many grams of water are required to produce 6.50 L of hydrogen gas at 25.0C and 755 mm Hg pressure according to the chemical equation shown below?BaH2(s) + 2 H2O(l) -> Ba(OH)2(aq) + 2 H2(g)A) 2.38 gB) 4.75 gC) 4.81 gD) 9.50 g

Q: How many liters of hydrogen gas can be generated by reacting 6.25 grams of barium hydride with water at 20C and 755 mm Hg pressure according to the chemical equation shown below?BaH2(s) + 2 H2O(l) -> Ba(OH)2(aq) + 2 H2(g)A) 0.148 LB) 0.540 LC) 1.08 LD) 2.17 L

Q: How many grams of calcium hydride are required to produce 2.28 L of hydrogen gas at 25.0C and 0.975 atm pressure according to the chemical equation shown below?CaH2(s) + 2 H2O(l) -> Ca(OH)2(aq) + 2 H2(g)A) 1.91 gB) 3.82 gC) 7.64 gD) 22.8 g

Q: Which transition metal hydride is commonly used in the purification of hydrogen gas? A) Cu B) Fe C) Pt D) Pd

Q: What is the oxidation number of N in NH3? A) -3 B) -1 C) +1 D) +3

Q: Covalent hydrides of the type MH3 are likely to form with elements of what group? A) 3A B) 4A C) 5A D) 6A

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