front 1 When should the latent heat of fusion be used?
| back 1 When a substance is changing from a solid (ice) to a liquid (water) or vice versa |
front 2 When should the latent heat of vaporization be used? | back 2 When a substance is changing from a liquid (water) to a gas (steam) or vice versa. |
front 3 A phase change from a solid to a gas is called__________. | back 3 Sublimation |
front 4 A phase change from a gas to a solid is called__________. | back 4 deposition |
front 5 A phase change from a gas to a liquid is called__________. | back 5 Condensation |
front 6 Which is generally greater in value: The latent heat of fusion or The latent heat of vaporization? | back 6 The latent heat of vaporization |
front 7 Why is the latent heat of vaporization generally greater in value than the latent heat of fusion? | back 7 The rearrangement is more extensive |
front 8 Define Critical temperature | back 8 Temperature at which the kinetic energy is greater than the attractive forces, and therefore gas cannot be made to liquefy no matter how high the the pressure. The density of the gas becomes indistinguishable from the density of the liquid. |
front 9 Define Supercritical fluid | back 9 any substance at a temperature and pressure above its critical point, where distinct liquid and gas phases do not exist. |
front 10 A certain metal bromide, MBr, crystallizes in a primitive cubic unit cell with bromide ions at the lattice points. If the metal ions occupy cubic holes, how many bromide ions surround each metal ion in th metal bromide? | back 10 8 |
front 11 T/F: According to the band theory as applied to metallic bonding, the valence electrons of representative metals are free to move within the solid leading to thermal conductivity. | back 11 True |
front 12 T/F: According to the band theory as applied to metallic bonding, the electrical conductivity of metallic solids decreases with increasing temperature. | back 12 True |
front 13 T/F: According to the band theory as applied to metallic bonding, the bonds between neighboring metal atoms can be described as localized electron pair bonds | back 13 False |
front 14 T/F: Most atomic solids have low melting points. | back 14 False |
front 15 T/F: The faces of a unit cell must all be at angles of 90° to each other. | back 15 False |
front 16 Define coordination number | back 16 the number of nearest neighbors at the same distance to a given atom |
front 17 formula for the edge length of a unit cell (d) | back 17 d=r√8 |
front 18 Areas of zero probability of finding an electron are called _________. | back 18 nodes/nodal surfaces |
front 19 What is Hund's rule? | back 19 the lowest energy configuration for an atom is the one having the maximum number of unpaired electrons allowed by the Pauli principle in a particular set of degenerate orbitals |
front 20 The Greeks proposed that matter consisted of four fundamental substances: | back 20 fire, earth, water, air |
front 21 The scientist whose alpha-particle scattering experiment led him to conclude that the nucleus of an atom contains a dense center of positive charge is_________. | back 21 Ernest Rutherford |
front 22 A quantitative observation_________. | back 22 contains a number and a unit |
front 23 What does the law of multiple proportions
state? | back 23 When two elements combine to form more than one compound, the mass of one element, which combines with a fixed mass of the other element, will always be ratios of whole numbers. |
front 24 If the Thomson model of the atom had been correct, Rutherford would have observed: | back 24 Alpha particles going through the foil with little or no deflection. |
front 25 Who measured the charge/mass ratio of the electron. | back 25 J.J. Thomson |
front 26 What did J.J. Thomson do? | back 26 Measure the charge/mass ratio of the electron. |
front 27 What did Rutherford's experiment with alpha particle scattering by gold foil establish? | back 27 protons are not evenly distributed throughout an atom. |
front 28 What scientist discovered the law of conservation of mass and is also called the father of modern chemistry? | back 28 Antoine Lavoisier |
front 29 T/F: The Rutherford experiment proved the Thomson "plum-pudding" model of the atom to be essentially correct. | back 29 False |
front 30 What component of atoms was discovered by Rutherford? | back 30 nucleus |
front 31 Who is credited with discovering the atomic nucleus? | back 31 Rutherford |
front 32 Who was the first chemist to perform truly quantitative experiments? | back 32 Robert Boyle |
front 33 A pure substance composed of two or more different elements is a(n) ________. | back 33 chemical compound |
front 34 What does the Law of Definite Composition state? | back 34 A given chemical compound always contains its component elements in fixed ratio (by mass). |
front 35 What chemist is credited for inventing a set of symbols for writing elements and a system for writing the formulas of compounds (and for discovering selenium, silicon, and thorium)? | back 35 Baron Jöns Jacob Berzelius |
front 36 A pure substance composed of two or more different elements is a(n) ________. | back 36 chemical compound |
front 37 How many of the following postulates of Dalton's atomic theory are still scientifically accepted? I. All atoms of the same element are identical. II. Compounds are combinations of different atoms. III. A chemical reaction changes the way atoms are grouped together. IV. Atoms are indestructible. | back 37 2 |
front 38 What states that at the same temperature and pressure, equal volumes of different gases contain an equal number of particles? | back 38 Avogadro's hypothesis |
front 39 Rutherford bombarded gold foil with alpha (a) particles and found that a small percentage of the particles were deflected. Which of the following was not accounted for by the model he proposed for the structure of atoms? | back 39 the total mass of the atom |
front 40 T/F: Cathode rays always move toward the cathode (negative electrode). | back 40 False |
front 41 What is a cathode ray? | back 41 a beam of electrons emitted from the cathode of a high-vacuum tube. |
front 42 T/F: The emission spectrum of hydrogen contains a continuum of colors. | back 42 False |
front 43 Excited hydrogen atoms radiate energy in the___________. | back 43 infrared, visible and ultraviolet regions. |
front 44 What is a reasonable criticism of the Bohr model of the atom? | back 44 It does not adequately predict the ionization energy of the valence electron(s) for elements other than hydrogen. |
front 45 T/F: It takes less energy to add an electron to nitrogen than to carbon because nitrogenwill be closer to achieving a noble gas configuration. | back 45 False |
front 46 T/F: It takes more energy to add an electron to fluorine than to oxygen because the radius of fluorine is smaller and more repulsion would occur in the p-orbitals. | back 46 False |
front 47 T/F: It takes more energy to add an electron to nitrogen than to carbon because of the extra repulsions that would occur in the 2p orbitals. | back 47 True |
front 48 T/F: Less energy is released in adding an electron to iodine than to chlorine because the radius of iodine is larger and the electron is added at a distance further from the nucleus. | back 48 True |
front 49 What type of spectrum, if any, would be produced if the light radiated by a heated atomic gas were to be dispersed through a prism? | back 49 discrete lines of different colors |
front 50 T/F: A 2p orbital is more penetrating than a 2s; i.e., it has a higher electron density near the nucleus and inside the charge cloud of a 1s orbital. | back 50 False |
front 51 The 2s orbital in calcium is more stable (more negative energy) than the 2p orbital even though the 2p orbital has its maximum electron density closer to the nucleus. The reason for this higher stability is: | back 51 due to its greater penetration, the 2s orbital has more electron density close to the nucleus than the 2p orbital |
front 52 What does the Aufbau principle state? | back 52 Electrons orbiting one or more atoms fill the lowest available energy levels before filling higher levels. |
front 53 T/F: Because Li is the strongest reducing agent of the alkali metals, it reacts most quickly with water of the alkali metals. | back 53 False |
front 54 T/F: Subshell energies are higher in multielectron atoms than the same subshell in the hydrogen atom. | back 54 False |
front 55 In the modern periodic table, the order in which the elements are placed is based on____________. | back 55 atomic number |
front 56 T/F: Atomic radius increases from top to bottom in a group and decreases from left to right across a period. | back 56 True |
front 57 After an atom has lost an electron it becomes a/an ______ and has a _______ charge. | back 57 cation, positive |
front 58 T/F: Larger bond order means greater bond strength. | back 58 True |
front 59 The concept of __________ is required for certain molecules because the localized electron model assumes electrons are located between a given pair of atoms in a molecule. | back 59 resonance |
front 60 T/F: When balancing a chemical equation, it is generally best to start with the least complicated molecules. | back 60 False |
front 61 T/F: For petroleum all of its hydrocarbon chains contain the same number of carbon atoms. | back 61 False |
front 62 A(n) ________ is a pure substance that is composed of only one type of atom. | back 62 element |
front 63 When a strontium salt is ignited, it burns with a red flame. The frequency of the light given off by this flame is greater than. | back 63 infrared light |
front 64 The __________ quantum number is related to the size and energy of the orbital. | back 64 principal (n) |
front 65 T/F: A state function does not depend on the system's past or future. | back 65 True |
front 66 Describe Boyle's Law | back 66 The pressure of an ideal gas is inversely proportional to its volume at constant temperature and number of moles. P1V1=P2V2 |
front 67 Describe Charles's law | back 67 Temperature of an ideal gas is directly proportional to its volume at a constant pressure and number of moles. V1/T1=V2/T2 |
front 68 Describe Gay-Lussac's law | back 68 Temperature of an ideal gas is directly proportional to its pressure at a constant volume and number of moles. P1/T1=P2/T2 |
front 69 Graphene was first prepared by removing layers from _________. | back 69 graphite |
front 70 T/F: Most metals occur as ionic solids. | back 70 False |
front 71 When liquid bromine is cooled to form a solid, which of the following types of solid would it form? | back 71 molecular |
front 72 T/F: For face-centered cubic cell, a metal atom is located at each of the eight lattice points, where it is shared equally between eight unit cells. | back 72 True |
front 73 T/F: For face-centered cubic cell, one metal atom is located on each face of the unit cell, where it is shared equally between four unit cells. | back 73 False |
front 74 T/F: For face-centered cubic cell, one metal atom is located at the center of the unit cell. | back 74 False |
front 75 In ionic solids, ________ occupy the lattice points. | back 75 ions |
front 76 What is the simplest formula of a solid containing A, B, and C atoms in a cubic lattice in which the A atoms occupy the corners, the B atoms the body-center position, and the C atoms the faces of the unit cell? | back 76 ABC3 |
front 77 Define Doping | back 77 Adding trace amounts of an element to a substance to modify its properties. |
front 78 An n-type semiconductor____________. | back 78 is doped with a valence e- rich element; "negative" |
front 79 A p-type semiconductor_____________. | back 79 is doped with a valence e- deficient element; "positive" |
front 80 Ephoton= | back 80 =hv=(hc)/λ |
front 81 λ= | back 81 =h/(mv) |
front 82 Describe the photoelectric effect | back 82 electrons are emitted from the surface of the metal when light strikes it. |
front 83 Who is credited with first measuring the charge of the electron? | back 83 Robert Millikan |
front 84 1 nanometer=how many meters? | back 84 =1x10-9 meters |
front 85 Describe Hess's Law. | back 85 Regardless of the multiple stages or steps of a reaction, the total enthalpy change for the reaction is the sum of all changes.=>enthalpy is a state function. |