Q&A Hero

Q: Gasoline is an example of A) a compound. B) an element. C) a heterogeneous mixture. D) a homogeneous mixture.

Q: Crude oil is an example of A) a compound. B) an element. C) a heterogeneous mixture. D) a homogeneous mixture.

Q: Which nuclide below is most likely to decay by electron capture? A) B) C) D)

Q: Which of the following nuclides is most likely to undergo beta decay? A) B) C) D)

Q: Which of the following elements would be expected to be particularly stable? A) B) C) D)

Q: In addition to a beta particle, what is the other product of beta decay of ? A) B) C) D)

Q: Beta decay of 32P produces a beta particle and A) 28Al. B) 31P. C) 32Si. D) 32S.

Q: The number of nucleons in a nucleus is A) 90. B) 144. C) 234. D) 324.

Q: Identify the chemical symbol of element Q in . A) Br B) Hg C) Pd D) Se

Q: How many electrons are in a neutral atom of bromine-81? A) 1 B) 35 C) 36 D) 81

Q: What is the element symbol for an atom that has 5 protons and 6 neutrons? A) B B) C C) H D) Na

Q: How many protons (p) and neutrons (n) are in an atom of barium-130? A) 56 p, 74 n B) 56 p, 130 n C) 74 p, 56 n D) 130 p, 56 n

Q: How many protons (p) and neutrons (n) are in an atom of ? A) 38 p, 52 n B) 38 p, 90 n C) 52 p, 38 n D) 90 p, 38 n

Q: Which of the following represent isotopes? A: [ ] B: [ ] C: [ ] D: [ ] A) A and B B) A and C C) A and D D) C and D

Q: Which are isotopes? An atom that has an atomic number of 20 and a mass number of 42 is an isotope of an atom that has A) an atomic number of 21 and a mass number of 42. B) an atomic number of 20 and a mass number of 40. C) 22 neutrons and 20 protons. D) 22 protons and 20 neutrons.

Q: Elements A and Q form two compounds, AQ and A2Q3. The mass ratio (mass Q)/(mass A) for AQ is 0. 291. What is the mass ratio (mass Q)/(mass A) for A2Q3? A) 0. 194 B) 0. 436 C) 2.29 D) 5.15

Q: A sample of pure calcium fluoride with a mass of 15.0 g contains 7.70 g of calcium. How much calcium is contained in 40.0 g of calcium fluoride? A) 2.27 g B) 7.70 g C) 15.0 g D) 20.5 g

Q: A sample of pure lithium carbonate contains 18.8.4% lithium by mass. What is the % lithium by mass in a sample of pure lithium carbonate that has twice the mass of the first sample? A) 9.40% B) 18.8% C) 37.6% D) 75.2%

Q: Sodium metal and water react to form hydrogen and sodium hydroxide. If 5.98 g of sodium react with water to form 0.26 g of hydrogen and 10.40 g of sodium hydroxide, what mass of water was involved in the reaction? A) 4.68 g B) 5.98 g C) 10.14 g D) 10.66 g

Q: Methane and oxygen react to form carbon dioxide and water. What mass of water is formed if 0.80 g of methane reacts with 3.2 g of oxygen to produce 2.2 g of carbon dioxide? A) 1.8 g B) 2.2 g C) 3.7 g D) 4.0 g

Q: Which is most likely to form a binary oxide with the formula M4O10 (where M = element A, B, C, or D)?A) element AB) element BC) element CD) element D

Q: Which is most likely to form a binary oxide with the formula M2O3 (where M = element A, B, C, or D)? A) element A B) element B C) element C D) element D

Q: Which is most likely to form a binary oxide with the formula MO3 (where M = element A, B, C, or D)? A) element A B) element B C) element C D) element D

Q: Which is most likely to form a binary oxide with the formula MO (where M = element A, B, C, or D)? A) element A B) element B C) element C D) element D

Q: In which pair are both formulas of binary fluorides of element D correct? A) DF2 and DF3 B) DF2 and DF6 C) DF3 and DF5 D) DF5 and DF6

Q: In which pair are both formulas of binary fluorides of element C correct? A) CF2 and CF3 B) CF2 and CF6 C) CF3 and CF5 D) CF5 and CF6

Q: Which is the correct formula of the binary fluoride of element B? A) BF2 B) BF3 C) BF5 D) BF6

Q: Which is the correct formula of the binary fluoride of element A? A) AF2 B) AF3 C) AF5 D) AF6

Q: Which drawing represents the ionic compound NH4ClO4? A) drawing (a) B) drawing (b) C) drawing (c) D) drawing (d)

Q: Which drawing represents the ionic compound KNO3? A) drawing (a) B) drawing (b) C) drawing (c) D) drawing (d)

Q: Which drawing represents the ionic compound CaCl2? A) drawing (a) B) drawing (b) C) drawing (c) D) drawing (d)

Q: Which drawing represents the ionic compound Na2CO3? A) drawing (a) B) drawing (b) C) drawing (c) D) drawing (d)

Q: Which drawing represents the ionic compound Mg3(PO4)2? A) drawing (a) B) drawing (b) C) drawing (c) D) drawing (d)

Q: Which elements commonly form covalent bonds? A) A and B B) A and C C) B and D D) C and D

Q: Which elements commonly form cations? A) A and B B) A and C C) B and D D) C and D

Q: Which elements commonly form anions? A) A and B B) A and C C) B and D D) C and D

Q: If shaded and unshaded spheres represent atoms of different elements, which of the above drawings most likely represents a molecular compound at room temperature and a pressure of 1 atm? A) drawing (a) B) drawing (b) C) drawing (c) D) drawing (d)

Q: If shaded and unshaded spheres represent atoms of different elements, which of the above drawings most likely represents an ionic compound at room temperature and a pressure of 1 atm? A) drawing (a) B) drawing (b) C) drawing (c) D) drawing (d)

Q: If shaded and unshaded spheres represent atoms of different elements, which of the above drawings most likely represents a molecular compound at room temperature and a pressure of 1 atm? A) drawing (a) B) drawing (b) C) drawing (c) D) drawing (d)

Q: If shaded and unshaded spheres represent atoms of different elements, which of the above drawings most likely represents an ionic compound at room temperature and a pressure of 1 atm? A) drawing (a) B) drawing (b) C) drawing (c) D) drawing (d)

Q: Give the molecular formula corresponding to the following ball-and-stick molecular representation of naphthalene (gray = C, unshaded = H). In writing the formula, list the atoms in alphabetical order. A) CH B) C5H4 C) C10H8 D) C10H10

Q: Give the molecular formula corresponding to the following ball-and-stick molecular representation of vitamin C (ascorbic acid) (gray = C, unshaded = H, black = O). In writing the formula, list the atoms in alphabetical order. A) CHO B) C3H4O3 C) C6H4O6 D) C6H8O6

Q: What kind of decay process is occurring in the decay of isotope D to isotope E in the figure shown above?

Q: What kind of decay process is occurring in the decay of isotope C to isotope D in the figure shown above?

Q: What kind of decay process is occurring in the decay of isotope B to isotope C in the figure shown above?

Q: What kind of decay process is occurring in the decay of isotope A to isotope B in the figure shown above?

Q: Tell the type of decay process occurring in the following nuclear reaction.

Q: Tell the type of decay process occurring in the following nuclear reaction.

Q: Tell the type of decay process occurring in the following nuclear reaction.

Q: Tell the type of decay process occurring in the following nuclear reaction.

Q: Tell the type of decay process occurring in the following nuclear reaction.

Q: Tell the type of decay process occurring in the following nuclear reaction.

Q: Which of the following figures represents ? Unshaded spheres represent neutrons and shaded spheres represent protons. A) figure (1) B) figure (2) C) figure (3) D) figure (4)

Q: Which of the following figures represents ? Unshaded spheres represent neutrons and shaded spheres represent protons. A) figure (1) B) figure (2) C) figure (3) D) figure (4)

Q: Which of the following figures represents ? Unshaded spheres represent neutrons and shaded spheres represent protons. A) figure (1) B) figure (2) C) figure (3) D) figure (4)

Q: If shaded and unshaded spheres represent atoms of different elements, as shown in drawing (1), which combination of drawings (2)-(4) represent the law of multiple proportions? A) only drawings (2) and (3) B) only drawings (2) and (4) C) only drawings (3) and (4) D) drawings (2), (3), and (4)

Q: If shaded and unshaded spheres represent atoms of different elements, as shown in drawing (1), which drawings (2)-(4) represent the law of multiple proportions? A) only drawings (2) and (3) B) only drawings (2) and (4) C) only drawings (3) and (4) D) drawings (2), (3), and (4)

Q: If shaded and unshaded spheres represent atoms of different elements, as shown in drawing (1), which drawings (2)-(4) represent the law of multiple proportions? A) only drawings (2) and (3) B) only drawings (2) and (4) C) only drawings (3) and (4) D) drawings (2), (3), and (4)

Q: If shaded and unshaded spheres represent atoms of different elements, as shown in drawing (1), which drawings (2)-(4) represent the law of multiple proportions? A) only drawings (2) and (3) B) only drawings (2) and (4) C) only drawings (3) and (4) D) drawings (2), (3), and (4)

Q: If shaded and unshaded spheres represent atoms of different elements, as shown in drawing (1), which drawings (2)-(4) represent the law of multiple proportions? A) only drawings (2) and (3) B) only drawings (2) and (4) C) only drawings (3) and (4) D) drawings (2), (3), and (4)

Q: Which of the following drawings depicts a chemical reaction consistent with Dalton's atomic theory? A) drawing a) B) drawing b) C) drawing c) D) drawing d)

Q: Which of the following drawings depicts a chemical reaction consistent with Dalton's atomic theory? A) drawing a) B) drawing b) C) drawing c) D) drawing d)

Q: Assume that the mixture of substances in drawing (1) undergoes a chemical reaction. Which of the drawings (2)-(4) represents a product mixture that is consistent with the law of mass conservation? A) drawing (2) B) drawing (3) C) drawing (4)

Q: Assume that the mixture of substances in drawing (1) undergoes a chemical reaction. Which of the drawings (2)-(4) represents a product mixture that is consistent with the law of mass conservation? A) drawing (2) B) drawing (3) C) drawing (4)

Q: Which of the above drawings represents a K+ ion? A) drawing (a) B) drawing (b) C) drawing (c) D) drawing (d)

Q: Which of the above drawings represents a Ca2+ ion? A) drawing (a) B) drawing (b) C) drawing (c) D) drawing (d)

Q: Which of the above drawings represents a Cl- ion? A) drawing (a) B) drawing (b) C) drawing (c) D) drawing (d)

Q: Which of the above drawings represents an Ar atom? A) drawing (a) B) drawing (b) C) drawing (c) D) drawing (d)

Q: If unshaded spheres represent sulfur atoms and shaded spheres represent oxygen atoms, which of the following drawings depicts a collection of sulfur trioxide molecules? A) drawing (a) B) drawing (b) C) drawing (c) D) drawing (d)

Q: Which of the following drawings represents a collection of acetylene (C2H2) molecules? The shaded spheres represent carbon atoms and the unshaded spheres represent hydrogen atoms. A) drawing (a) B) drawing (b) C) drawing (c) D) drawing (d)

Q: Which of the above drawings represents a mixture? A) drawing (a) B) drawing (b) C) drawing (c)

Q: Which of the above drawings represents a pure compound? A) drawing (a) B) drawing (b) C) drawing (c)

Q: Which of the above drawings represents a pure element? A) drawing (a) B) drawing (b) C) drawing (c)

Q: What are the names of the ions Ba2+, Sn2+, and Se2-? A) barium, tin, and selenium B) barium, tin(II), and selenide C) barium(II), tin(II), and selenium(II-) D) barous, stannous, and selenide

Q: KH2PO4 is A) hydropotassium phosphate. B) potassium dihydrogen phosphate. C) potassium diphosphate. D) potassium hydrogen(II) phosphate.

Q: The thiosulfate ion is A) HS-. B) HSO42-. C) SO52-. D) S2O32-.

Q: The chemical formula for calcium nitride isA) Ca(NO3)2.B) Ca(NO2)2.C) Ca3N2.D) CaN2.

Q: The ion NO2- is named A) nitrate ion. B) nitrite ion. C) nitrogen dioxide ion. D) nitrogen(II) oxide ion.

Q: The compound, NO2, is named A) nitrate. B) nitrite. C) nitrogen dioxide. D) nitrogen(IV) oxide.

Q: The ions ClO4-, ClO3-, ClO2-, and ClO- are named respectively A) hypochlorate, chlorate, chlorite, perchlorite. B) hypochlorite, chlorite, chlorate, perchlorate. C) perchlorate, chlorate, chlorite, hypochlorite. D) perchlorite, chlorite, chlorate, hypochlorate.