Q&A Hero

Q: What is the correct formula for calcium phosphate? A) Ca3P2 B) Ca2(PO4)3 C) Ca3(PO4)2 D) Ca2P3

Q: The anion in the common ionic substance NaHCO3 is A) CO32-. B) H+. C) Na+. D) HCO3-.

Q: Which of the following elements commonly forms an ion with a 1- charge?A) AgB) NC) BrD) Na

Q: The ionic compound made of Fe3+ and CO32- ions would have the formula A) Fe3(CO3)2. B) FeCO3. C) Fe2(CO3)3. D) none of these

Q: Which two elements are most likely to combine with one another to form an ionic compound? A) B and Cl B) Ra and Br C) Mg and Ca D) S and O

Q: Which of the following ions would never form in chemical reactions? A) F2- B) Al3+ C) O2- D) N3-

Q: Which of the following ions is isoelectronic with a neon atom? A) N3- B) Li+ C) Cl- D) F2-

Q: Which of the following ions is not isoelectronic with the other three? A) Cl- B) K+ C) Br- D) P3-

Q: The Lewis symbol of which of the following elements has a single dot on each of the four sides of the element's symbol? A) Helium B) Carbon C) Beryllium D) None of these

Q: A Group 6A nonmetal would be most likely to form an ionic bond with an element of Group A) 4A. B) 8A. C) 2A. D) 5A.

Q: The ionic charge of the nitrite ion in Al(NO2)3, aluminum nitrite, must be A) 3+. B) 1". C) 3". D) 1+.

Q: Except for hydrogen and helium, atoms in chemical combination tend to have ______________ electrons in their outer shell. A) 8 B) 14 C) 6 D) 2

Q: Combinations of atoms from the far right side of the periodic table with atoms from the far left side usually form ______________ compounds. A) organic B) ionic C) covalent D) polar

Q: If a compound is solid, has a high melting point, conducts electricity in the liquid phase, and dissolves in water, it is most likely to be a(n)______________ compound. A) intermediate B) organic C) covalent D) ionic

Q: If atoms unite by transfer of electrons, they form A) an organic compound. B) an ionic compound. C) a polar molecule. D) a covalent compound.

Q: The Lewis symbol would be characteristic of which group?A) 6AB) 8AC) 3AD) 7A

Q: The Lewis symbol would be characteristic of which group?A) 6AB) 8AC) 3AD) 7A

Q: The Lewis symbol would be characteristic of which group?A) 6AB) 1AC) 3AD) 7A

Q: The Lewis symbol would be characteristic of which group?A) 6AB) 2AC) 3AD) 5A

Q: The Lewis symbol would be characteristic of which group? A) 2A B) 4A C) 3A D) 5A

Q: The Lewis symbol would be characteristic of which group?A) 2AB) 4AC) 3AD) 1A

Q: The Lewis symbol would be characteristic of which group?A) 2AB) 4AC) 6AD) 1A

Q: The Lewis symbol X- would be characteristic of which group? A) 2A B) 4A C) 6A D) 1A

Q: The Lewis symbol -X- would be characteristic of which group? A) 2A B) 4A C) 6A D) 1A

Q: What is the formula of the compound formed from the ions of calcium and bromine? A) CaBr3 B) CaBr C) CaBr2 D) Ca2Br3 E) None of these

Q: What is the formula of the compound formed from the ions of aluminum and oxygen? A) Al2O3 B) AlO C) AlO3 D) None of these

Q: What is the formula of a compound formed from the ions M1+ and X1-? A) M2X B) MX C) M2X2 D) MX2

Q: What is the formula of a compound formed from the ions M2+ and X3-? A) MX B) M3X2 C) M2X3 D) M6X6

Q: What is the formula of a compound formed from the ions M3+ and X1-? A) M3X B) MX C) M2X3 D) MX3

Q: What is the formula of a compound formed from the ions M3+ and X3-? A) M2X B) MX C) M2X3 D) MX2

Q: What is the formula of a compound formed from the ions M3+ and X2-? A) M2X B) MX C) M2X3 D) MX2

Q: What is the formula of a compound formed from the ions M2+ and X2-? A) M2X B) MX C) M2X2 D) MX2

Q: What is the formula of a compound formed from the ions M1+ and X3-? A) M3X B) MX3 C) MX D) None of these

Q: What electric charge is characteristic for an ion of S?A) 6+B) 0C) 2-D) 2+

Q: What electric charge is characteristic for an ion of F?A) 7+B) 0C) 1-D) 1+

Q: What electric charge is characteristic for an ion of Cl?A) 7+B) 0C) 1-D) 1+

Q: What electric charge is characteristic for an ion of O?A) 6+B) 0C) 2-D) 2+

Q: The octet rule states that the formula for a compound is derived by A) using a minimum of 8 atoms. B) using exactly 8 bonds in the formula unit. C) having all atoms or ions get noble gas electron configurations. D) having a net charge of magnitude 8.

Q: A general principle of ionic compound formation is that the total ionic charge in the formula unit must beA) 0.B) no greater than that of the metal ion.C) between +4 and -4.D) no less than that of the nonmetal ion.

Q: Which of the following was not a part of Dalton's atomic theory? A) Each element is composed of atoms, which are identical for that element. B) The reactivity of elements involves changes in their electron configuration. C) Chemical combination is the bonding of a definite number of atoms of each of the combining elements. D) No atoms are gained, lost, or changed in identity during a chemical reaction.

Q: For a compound composed of ions, the smallest combination of ions that gives the formula of the compound is called a A) molecule. B) polyionic atom. C) polyatomic ion. D) formula unit.

Q: The atomic theory was revived and put on a solid experimental foundation in about 1803 by A) Proust. B) Dalton. C) Boyle. D) Lavoisier.

Q: A likely ratio of the masses of oxygen in two different compounds of tin and oxygen, both of which contain the same mass of tin, is A) 1.42 to 1. B) 3.11 to 1. C) 3.77 to 1. D) 2 to 1.

Q: Element A, mass 19.00 g, reacts exactly with 7.00 g of element B to form 26.00 g of compound AB. If 57.00 g of element A is reacted with 33.00 g of element B to form the same compound, what mass of compound AB will be formed? A) 19.00 g B) 12.00 g C) 11.00 g D) 31.00 g

Q: Element A, mass 10.00 g, reacts exactly with 2.00 g of element B to form 12.00 g of compound AB. If 5.00 g of element A is reacted with 2.00 g of element B to form the same compound, what mass of compound AB will be formed? A) 7.00 g B) 6.00 g C) 17.00 g D) 12.00 g

Q: Element A, mass 5.00 g, reacts exactly with 2.00 g of element B to form 7.00 g of compound AB. If 10.00 g of element A are reacted with 2.00 g of element B to form the same compound, what mass of compound AB will be formed? A) 7.00 g B) 5.00 g C) 17.00 g D) 12.00 g

Q: When sodium and chlorine react to form sodium chloride, an ionic compound, A) each sodium atom gains two electrons. B) each sodium atom gains one electron. C) each chlorine atom gains one electron. D) each chlorine atom gains two electrons.

Q: When sodium and chlorine react to form sodium chloride, an ionic compound, A) each sodium atom loses two electrons. B) each sodium atom loses one electron. C) each chlorine atom loses one electron. D) each chlorine atom loses two electrons.

Q: When potassium and sulfur react to form potassium sulfide, an ionic compound, A) each sulfur atom loses two electrons. B) each sulfur atom loses one electron. C) each potassium atom loses one electron. D) each potassium atom loses two electrons.

Q: Suppose 65 g of reactant A is mixed with 71 g of reactant B. After a chemical reaction takes place between A and B, which statement is correct? A) The total mass of products plus any unreacted reactants will be 136 g. B) The total mass of products plus any unreacted reactants will be less than 136 g. C) The total mass of products plus any unreacted reactants will be more than 136 g. D) The total mass of products will be 136 g.

Q: Suppose 25 g of reactant A is mixed with 45 g of reactant B. After a chemical reaction takes place between A and B, which statement is correct? A) The total mass of products plus any unreacted reactants will be 70 g. B) The total mass of products plus any unreacted reactants will be less than 70 g. C) The total mass of products plus any unreacted reactants will be more than 70 g. D) The total mass of products will be 70 g.

Q: A compound consists of only magnesium, carbon, and oxygen. If the percentage by mass of Mg is 74.9% and that of C is 19.2%, what is the percentage by mass of O? A) 94.1% B) 5.9% C) 55.7% D) 83.7% E) None of the above

Q: A compound consists of only magnesium, carbon, and oxygen. If the percentage by mass of Mg is 28.8% and that of C is 14.2%, what is the percentage by mass of O? A) 16.0% B) 57.0% C) 43.0% D) 22.5% E) None of the above

Q: Another name for solid carbon dioxide is A) heavy water. B) Epsom salt. C) dry ice. D) quicksilver.

Q: The percentage by mass of carbon A) would be the same in CO as in CO2. B) would be greater in CO than in CO2. C) would be less in CO than in CO2. D) cannot be determined without additional information.

Q: The percentage by mass of chlorine A) would be the same in FeCl3 as in FeCl2. B) would be greater in FeCl3 than in FeCl2. C) would be less in FeCl3 than in FeCl2. D) cannot be determined without additional information.

Q: The law of definite proportions states that different samples of a pure compound always contain the same elements in the same proportion by A) mass. B) atoms. C) atomic number. D) volume.

Q: The percentage by mass of carbon in diamond is about A) 25%. B) 75%. C) 100%. D) 20%.

Q: The percentage by mass of carbon in methane, CH4, is about A) 25%. B) 75%. C) 80%. D) 20%.

Q: The percentage by mass of hydrogen in methane, CH4, is about A) 25%. B) 75%. C) 80%. D) 20%.

Q: The ratio by mass of carbon to hydrogen in 100 g of a certain compound is 6 to 1. The ratio in 200 g of the same compound will be A) 24 to 1. B) 6 to 1. C) 12 to 1. D) none of these.

Q: The percentage composition by mass of nitrogen dioxide is approximately A) 43% N and 57% O. B) 33% N and 67% O. C) 30% N and 70% O. D) 47% N and 53% O.

Q: The percentage composition by mass of water is approximately A) 2% H and 1% O. B) 11% H and 89% O. C) 1% H and 99% O. D) 2% H and 16% O.

Q: The formula mass of sulfuric acid, H2SO4, is A) 98 u. B) 100 u. C) 66 u. D) 7 u.

Q: The formula mass of water, H2O, is A) 18 u. B) 9 u. C) 10 u. D) 17 u.

Q: The formula mass of calcium hydroxide, Ca(OH)2, is A) 74.1 u. B) 38.1 u. C) 57.1 u. D) 58.1 u.

Q: What is the formula mass of ammonium phosphide, (NH4)3P? A) 85.0 u B) 49.0 u C) 48.0 u D) 57.0 u

Q: An element that tends to gain electrons during chemical reactions is probably A) a semimetal. B) a nonmetal. C) an actinide. D) a metal.

Q: A substance of unknown composition is heated in a sealed container. As a result, the mass of the container and its contents A) increases. B) decreases. C) remains the same. D) Any of these could occur.

Q: A substance of unknown composition is heated in an open container. As a result, the mass of the container and its contents A) decreases. B) remains the same. C) increases. D) Any of these could occur.

Q: What person is known as the "father of chemistry" for his many contributions, including the law of conservation of mass? A) Boyle B) Lavoisier C) Mendeleev D) Dalton

Q: The force responsible for chemical bonding is A) nuclear. B) electromagnetic. C) none of these. D) gravitational.

Q: Draw the Lewis structure for Freon-12, CF2Cl2.

Q: Identify each of the following molecules as either polar or nonpolar. a. ClO b. N2 c. Cl2 d. CH4

Q: Identify each of the following compounds as either ionic or covalent. a. KBr b. CCl4 c. NaF d. C2H4

Q: How many covalent bonds would be formed by an atom of each of the following elements? a. C b. H c. F d. Ne

Q: Predict the ionic charge for an ion of each of the following representative elements.a. Lib. Sec. Krd. N

Q: Predict the formula and draw the Lewis structure of magnesium bromide.

Q: Calculate the percentage composition by mass (to the nearest 0.1) of each element in sodium sulfide, Na2S.

Q: Calculate the percentage composition by mass (to the nearest 0.1) of each element in aspirin, C9H8O4.