Q&A Hero

Q: Which orbitals have two nodal planes passing through the nucleus? A) s B) p C) d D) all in the third shell

Q: Which orbitals do not have a node at the nucleus? A) all beyond the first shell B) all but s C) none D) s

Q: An electron in a 4p orbital can have a wave function with which of the following set of quantum numbers, (n, l, ml, ms)? A) (4, 0, 0, 1/2) B) (4, 1, "1, "1/2) C) (5, 4, 1, "1/2) D) (5, 4, 4, 1/2)

Q: Which of the following is not a valid set of quantum numbers? A) n = 2, l = 1, ml = 0, and ms = -1/2 B) n = 2, l = 1, ml = -1, and ms = -1/2 C) n = 3, l = 0, ml = 0, and ms = 1/2 D) n = 3, l = 2, ml = 3, and ms = 1/2

Q: If the quantum number ms had possible values 1, 2, what would be the maximum number of electrons that be placed in a single orbital? A) one B) two C) three D) four

Q: How many electrons can a single orbital hold? A) 2n B) 2 C) 2l + 1 D) 8

Q: How many orbitals are there in the seventh shell? A) 6 B) 7 C) 21 D) 49

Q: What are the possible values of n and ml for an electron in a 5d orbital? A) n = 1, 2, 3, 4, or 5 and ml = 2 B) n = 1, 2, 3, 4, or 5 and ml = -2, -1, 0, +1, or +2 C) n = 5 and ml = 2 D) n = 5 and ml = -2, -1, 0, +1, or +2

Q: The number of orbitals in a given subshell, such as the 5d subshell, is determined by the number of possible values of A) n. B) l. C) ml. D) ms.

Q: How many h orbitals are allowed in a given shell? A) 5 B) 6 C) 11 D) 13

Q: The subshell designations follow the alphabet after f. What is the first shell in which an h orbital would be allowed? A) fifth B) sixth C) seventh D) eighth

Q: How many subshells are there in the shell with n = 6? A) 5 B) 6 C) 15 D) 36

Q: What are the possible values of l if n = 5? A) 5 B) 0, 1, 2, 3, or 4 C) -4, -3, -2, -1, 0, +1, +2, +3, or +4 D) -5, -4, -3, -2, -1, 0, +1, +2, +3, +4, or +5

Q: For an electron in a given atom, the larger n, the A) larger the average distance from the nucleus and the higher the orbital energy. B) larger the average distance from the nucleus and the lower the orbital energy. C) smaller the average distance from the nucleus and the higher the orbital energy. D) smaller the average distance from the nucleus and the lower the orbital energy.

Q: Which of the following is true? A) The Bohr atom is the model currently accepted for electrons in atoms. B) Electrons travel around the nucleus in circular orbits. C) There is a 5% chance of finding an electron in an atom outside its orbital. D) The square of the wave function gives the probability of finding the electron within a given region of space around the nucleus.

Q: The intensity of a beam of light is related to its A) frequency. B) relative number of photons. C) speed. D) wavelength.

Q: An oxygen molecule has a mass of 5.3 10-26 kg and an approximate diameter of 3.6 10-10 m. If the molecule is moving at 400 m/s (1000 mph) with an uncertainity in velocity of 1 m/s, the uncertainty in position A) is less than or equal to 5 10-26 m. B) must be equal to 5 10-26 m. C) must be equal to 1 10-9 m. D) is greater than or equal to 1 10-9 m.

Q: A baseball with a mass of 150 g is moving at a velocity of 40 m/s (90 mph). If the uncertainity in the velocity is 0.1 m/s, the uncertainty in position A) may be zero. B) must be less than or equal to 4 10-33 m. C) must be 4 10-33 m. D) must be greater than or equal to 4 10-33 m.

Q: According to the Heisenberg uncertainty principle, A) the position of a particle cannot be measured precisely. B) the momentum of a particle cannot be measured precisely. C) neither the position nor the momentum of a particle can be measured precisely. D) the position and momentum of a particle can be measured precisely, but not at the same time.

Q: Which of the following is not true? A) All moving objects have wave characteristics. B) For objects moving at a given speed, the larger the mass, the shorter the wavelength. C) The de Broglie relation and the Heisenberg uncertainty principle apply only to small particles. D) The Heisenberg uncertainty principle is an inequality.

Q: The wave characteristics of a large, moving object, such as an automobile, are difficult to observe because the A) energy is not quantized. B) energy is quantized, but the spacing between energy levels is small. C) wavelength is very large. D) wavelength is very small.

Q: What is the de Broglie wavelength of a 300-g object moving at a velocity of 50 m/s (about 100 mph)? A) 4 10-38 m B) 4 10-35 m C) 4 109 m D) 4 1012 m

Q: An old copper penny has a mass 3 1022 times that of a copper atom. Compare the de Broglie wavelength of a penny moving at 0.5 m/s to that of a copper atom moving 104 times as fast. The wavelength for the A) copper atom is 3 1018 times that of the penny. B) copper atom is 3 1026 times that of the penny. C) penny is 3 1018 times that of the copper atom. D) penny is 3 1026 times that of the copper atom.

Q: What is the de Broglie wavelength of an electron (m = 9.11 10-31 kg) moving at a velocity of 3.0 107 m/s (10% of the speed of light)? A) less than 3.9 10-12 m B) 2.4 10-11 m C) 3.3 10-8 m D) greater than 1.1 10-4 m

Q: Of the following, which has the shortest de Broglie wavelength? A) an airplane moving at a velocity of 300 mph B) a helium nucleus moving at a velocity of 1000 mph C) a nitrogen molecule moving at a velocity of 1000 mph D) a nitrogen molecule moving at a velocity of 5000 mph

Q: Which of the following is not quantized? A) the charge on a monatomic ion B) the distance between two objects C) the population of the United States D) the static charge on a balloon rubbed with wool

Q: A quantized variable A) can be continuously varied. B) can only assume certain values. C) consists of photons. D) is extremely small.

Q: What is a quantum of light called? A) the amplitude B) the frequency C) a photon D) the wavelength

Q: The work function of copper metal is 437 kJ/mol. What is the maximum wavelength of light that can be used to eject electrons from copper? A) 2.65 m B) 2.74 m C) 6.36 m D) 5.42 m

Q: The work function of iron metal is 451 kJ/mol. What is the maximum wavelength of light that can be used to eject electrons from iron? A) 3.39 m B) 5.42 m C) 6.36 m D) 2.65 m

Q: A person is most likely to experience serious biological effects when exposed to which of the following forms of electromagnetic radiation? A) microwaves B) infrared C) ultraviolet D) x rays

Q: According to the Balmer-Rydberg equation, electromagnetic radiation with wavelength λ = 486.1 nm will be absorbed when an electron undergoes which of the following transitions?A) m = 2 -> n = 3B) m = 2 -> n = 4C) n = 3 -> m = 2D) n = 4 -> m = 2

Q: According to the Balmer-Rydberg equation, electromagnetic radiation with the shortest wavelength will be emitted when an electron undergoes which of the following transitions?A) m = 1 -> n = 2B) m = 2 -> n = 3C) n = 2 -> m = 1D) n = 3 -> m = 2

Q: What is the frequency of a helium-neon laser light with a wavelength of 632.8 nm? The speed of light is 3.00 108 m/s. A) 4.74 1014 s-1 B) 4.74 105 s-1 C) 2.11 10-15 s-1 D) 1.58 10-15 s-1

Q: Arrange the following spectral regions in order of increasing energy: infrared, microwave, ultraviolet, visible. A) microwave < infrared < visible < ultraviolet B) microwave < visible < infrared < ultraviolet C) ultraviolet < infrared < visible < microwave D) ultraviolet < visible < infrared < microwave

Q: The greater the energy of a photon, the A) longer the wavelength and the higher the frequency. B) longer the wavelength and the lower the frequency. C) shorter the wavelength and the higher the frequency. D) shorter the wavelength and the lower the frequency.

Q: Arrange the following spectral regions in order of increasing wavelength: infrared, microwave, ultraviolet, visible. A) microwave < infrared < visible < ultraviolet B) microwave < visible < infrared < ultraviolet C) ultraviolet < infrared < visible < microwave D) ultraviolet < visible < infrared < microwave

Q: Which of the following figures represents H? 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: Tritium, H, is formed in the upper atmosphere when N captures a neutron and then decays. What is the other product of this reaction? A) C B) C C) B D) B

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

Q: Which reaction below represents Ti decay by electron capture? A) Ti + e → Ti B) Ti + e → Ti C) Ti + e → Ti D) Ti + e → Sc

Q: Which reaction below represents Th decay by alpha emission? A) Th → He + Ra B) Th → He + Ra C) Th → p + Ac D) Th → n + Th

Q: Which reaction below represents O decay by positron emission? A) O → e + Ra B) O → e + N C) O → e + O D) O → e + O

Q: Which of the following decay processes give a product nuclide whose atomic number is one less than the starting nuclide? A) alpha decay B) beta decay and positron decay C) gamma decay and beta decay D) positron decay and electron capture

Q: Which one of the following processes does not result in transmutation to another element? A) alpha emission B) beta emission C) electron capture D) gamma emission

Q: Which of the following statements about electron capture is false? A) The electron is used to convert a proton to a neutron. B) The electron involved is most likely an outer shell valence electron. C) In electron capture decay, the atomic number decreases by one. D) In electron capture decay, the mass number remains unchanged.

Q: Which of the following statements about positrons is false? A) The positron has same mass as an electron. B) A positron is ejected from the nucleus during the conversion of a proton into a neutron. C) A positron is a positive electron. D) When positron emission occurs, the atomic number of the nucleus increases.

Q: Positron emission changes the atomic number of an element by A) -2. B) -1. C) +1. D) +2.

Q: A positron is A) n. B) p. C) e. D) e.

Q: Gamma radiation can be described as A) a helium nucleus. B) a negatively charged free electron. C) high energy electromagnetic radiation. D) a positively charged free electron.

Q: Which of the following statements about gamma radiation is false? A) It almost always accompanies alpha or beta emission. B) It is a mechanism to release excess energy in the nucleus. C) Gamma rays are high energy photons. D) The mass number decreases by one with each gamma emitted.

Q: Beta decay of 24Na produces a beta particle and A) 20F. B) 23Na. C) 24Ne. D) 24Mg.

Q: When a substance decays by beta emission, the mass number of the nucleus ________ and the atomic number ________. A) decreases by 1, remains the same B) increases by 1, remains the same C) remains the same, decreases by 1 D) remains the same, increases by 1

Q: A beta particle is A) e. B) e. C) p. D) He.

Q: The nuclear decay process that involves the particle having the greatest mass is ________ emission. A) alpha B) beta C) gamma D) positron

Q: When a substance decays by alpha radiation, the mass number of the nucleus ________ and the atomic number ________. A) increases by 4, increases by 2 B) reduces by 4, reduces by 2 C) increases by 2, increases by 4 D) reduces by 2, reduces by 4

Q: An alpha particle is A) H+. B) H+. C) H+. D) He2+.

Q: Which of the following statements is not correct when balancing a nuclear equation? I. The mass numbers must be conserved on both sides of the reaction arrow. II. The ionic charges must be conserved on both sides of the reaction arrow. III. The atomic numbers must be conserved on both sides of the reaction arrow. IV. The elements must be the same on both sides of the reaction arrow. A) II only B) II and III C) I and III D) II and IV

Q: "Isotopes" are atoms with the same number of ________ but different number of ________. A) electrons, protons B) neutrons, protons C) protons, electrons D) protons, neutrons

Q: The number of neutrons in Fe2+ is A) 26. B) 29. C) 53. D) 55.

Q: The number of nucleons in a U2+ nucleusis A) 92. B) 144. C) 236. D) 328.

Q: The number of nucleons in an atom or ion is the same as the A) atomic number. B) charge on the atom or ion. C) mass number. D) none of these

Q: The term "nucleons" refers to the number of ________ in the atom. A) neutrons B) protons C) protons and neutrons D) protons, neutrons, and electrons

Q: Which statement about nuclear reactions is true? A) New elements are never produced in a nuclear reaction. B) Nuclear reactions involve valence electrons. C) The rate of a nuclear reaction is affected by catalysts. D) Tremendous amounts of energy are involved in nuclear reactions.

Q: How many moles and how many atoms of zinc are in a sample weighing 34.9 g? A) 0.533 mol, 8.85 atoms B) 0.533 mol, 3.21 atoms C) 1.87 mol, 3.10 atoms D) 1.87 mol, 1.13 atoms

Q: 24.0 g of which element contains the greatest number of atoms? A) B B) C C) N D) O

Q: One mole of which element has the smallest mass? A) Co B) Cu C) Ni D) Zn

Q: What is the standard isotope that is used to define the number of atoms in a mole? A) 1H B) 12C C) 16O D) 20Ne

Q: The element antimony has an atomic weight of 121.757 amu and only two naturally-occurring isotopes. One isotope has an abundance of 57.30% and an isotopic mass of 120.904 amu. Based on these data, what is the mass of the other isotope? A) 121.8 amu B) 122.4 amu C) 122.6 amu D) 122.9 amu

Q: An element has two naturally occurring isotopes. One has an abundance of 37.40% and an isotopic mass of 184.953 amu, and the other has an abundance of 62.60% and a mass of 186.956 amu. What is the atomic weight of the element? A) 185.7 amu B) 186.0 amu C) 186.2 amu D) 187.0 amu

Q: The smallest sample of carbon atoms that can be observed with the naked eye has a mass of approximately 2 10-8 g. Given that 1 g = 6.02 1023 amu, and that carbon has an atomic weight of 12.01 amu, determine the number of carbon atoms present in the sample. A) 1 1015 B) 1 1016 C) 1 1017 D) 6 1023