Chemistry 1211K Test III. MULTIPLE CHOICE (3 points each, put answers on the answer sheet).

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1 A Chemistry 1211K Test III MULTIPLE CICE (3 points each, put answers on the answer sheet). 1) f the following, which one is a state function? A) q B) C) w D) heat E) none of the above 2) The reaction 4Al (s) (g) 2 Al 2 3 (s) = kj is, and therefore heat is by the reaction. A) endothermic, released B) exothermic, absorbed C) endothermic, absorbed D) exothermic, released E) thermoneutral, neither released nor absorbed 3) The value of o for the reaction below is -336kJ. Calculate the heat (kj) released when 23.0g of Cl is formed. C 4 (g) + 3 Cl 2 (g) CCl 3 (l) + 3Cl(g) A) -336kJ B) x 10 3 kj C) 177kJ D) 211kJ E) -70.7kJ 4) For which one of the following equations is o rxn equal to o f for the product? A) Xe (g) + 2 F 2 (g) XeF 4 (g) B) C 4 (g) + 2 Cl 2 (g) C 2 Cl 2 (l) + 2Cl (g) C) C (diamond) + 2 (g) C 2 (g) D) N 2 (g) + 3 (g) N 2 3 (g) E) 2C (g) + 2 (g) 2C 2 (g) 5) Given the data in the table below, o rxn for the reaction is kj. 2 Ag 2 S (s) + 2 (g) 2 Ag 2 (s) + 2S (s) Substance o f (kj/mol) Ag 2 (s) Ag 2 S (s) (g) 0 S (s) 0 A) -3.2 B) -1.6 C) +3.2 D) +1.6 E) ) A 5.00-g sample of liquid water at 25.0 C is heated by the addition of 84.0 J of energy. The final temperature of the water is o C. The specific heat capacity of liquid water is 4.18 J/g-K. A) 95.2 B) 29.0 C) D) 4.02 E) ) The photoelectric effect is. A) the total reflection of light by metals giving them their typical luster B) a relativistic effect C) the production of heat by silicon solar cells when exposed to sunlight D) the ejection of electrons by a metal when struck by light E) the darkening of photographic film when exposed to an electric field

2 8) The lines in the emission spectrum of hydrogen result from. A) electrons given off by hydrogen as it cools B) protons given off when hydrogen burns C) decomposing hydrogen atoms D) electrons given off by hydrogen when it burns E) energy given off in the form of visible light when an electron moves from a higher energy state to a lower energy state 9) The uncertainty principle states that. A) it is impossible to know the exact position and momentum of an electron B) it is impossible to know anything with certainty C) matter and energy are really the same thing D) it is impossible to know how many electrons there are in an atom E) there can only be one uncertain digit in a reported number 10) Which of the subshells below do not exist due to the constraints upon the azimuthal quantum number? A) 2s B) 2p C) 2d D) all of the above E) none of the above 11) The ground state electron configuration of Fe is. A) 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 B) 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 6 C) 1s 2 2s 2 3s 2 3p 10 D) 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 4d 6 E) 1s 2 2s 2 3s 2 3p 6 3d 6 12) The valence shell of the element X contains 2 electrons in a 5s subshell. Below that shell, element X has a partially filled 4d subshell. What type of element is X? A) transition metal B) main group element C) halogen D) alkali metal E) chalcogen 13) The element that corresponds to the electron configuration 1s 2 2s 2 2p 6 is. A) beryllium B) lithium C) magnesium D) sodium E) neon 14) In which set of elements would all members be expected to have very similar chemical properties? A) N,, F B) Ne, Na, Mg C) S, Se, Si D), S, Se E) Na, Mg, K 15) Atomic radius generally increases as we move. A) down a group; the period position has no effect B) down a group and from right to left across a period C) up a group and from left to right across a period D) up a group and from right to left across a period E) down a group and from left to right across a period 16) Which of the following correctly lists the five atoms in order of increasing size (smallest to largest)? A) F < Br < Ge < K < Rb B) F < Ge < Br < K < Rb C) F < Br < Ge < Rb < K D) F < K < Ge < Br < Rb E) F < K < Br < Ge < Rb

3 17) Which of the following correctly represents the second ionization of aluminum? A) Al (g) Al + (g) + e - B) Al + (g) Al 2+ (g) + e - C) Al- (g) + e - Al 2- (g) D) Al + (g) + e - Al 2+ (g) E) Al + (g) + e - Al (g) 18) Which ion in the isoelectronic series below has the smallest radius in a crystal? A) Na + B) 2- C) Al 3+ D) N 3- E) F - 19) Which one of the following compounds would produce an acidic solution when dissolved in water? A) Ca B) Sr C) Mg D) Na 2 E) C 2 20) In nature, the noble gases exist as A) monatomic gaseous atoms B) the gaseous fluorides C) the sulfides D) alkali metal salts E) solids in rocks and in minerals 21) Based on the octet rule, iodine most likely forms an ion. A) I 4- B) I + C) I 4+ D) I - E) I 2+ 22) Elements from opposite sides of the periodic table tend to form. A) covalent compounds that are gaseous at room temperature B) ionic compounds C) covalent compounds D) compounds that are gaseous at room temperature E) homonuclear diatomic compounds 23) f the atoms below, is the least electronegative. A) F B) Rb C) Si D) Ca E) Cl 24) The formal charge on nitrogen in N 3 - is. N _ A) 0 B) -1 C) +1 D) -2 E) +2 25) A valid Lewis structure of cannot be drawn without violating the octet rule. A) PF 3 B) NF 3 C) I - D) S 4 2- E) Sb 2+

4 Problems (SW ALL WRK N TIS PAPER) (5 points) Give the Lewis structure for the following molecules or ions: Formula Lewis Structure PCl 3 Cl P Cl Cl B 4 - B - As 3 3- As 3-

5 (10 points) Calculate the standard enthalpy of formation of gaseous diborane (2B(s) (g) B 2 6 (g)) using the following thermochemical information. Reaction 4B(s) (g) 2B 2 3 (s) 2 2 (g) + 2 (g) 2 2 (l) B 2 6 (g) (g) B 2 3 (s) + 2 (l) o rxn kJ kJ kJ 1/2 (4B(s) (g) 2B 2 3 (s)) ½( kJ) 3/2 (2 2 (g) + 2 (g) 2 2 (l)) 3/2(-571.7kJ) B 2 3 (s) (l) B 2 6 (g) (g) -( kJ) 2B(s) + 3/2 2 (g) B 2 3 (s) 3 2 (g) + 3/2 2 (g) 3 2 (l) B 2 3 (s) (l) B 2 6 (g) (g) 2B(s) (g) B 2 6 (g) kJ kJ) kJ 35.3kJ (5 points) Give the electron configuration for the following gas phase atoms: Phosphorus (P) 2s 2 2p 6 3s 2 3p 3 or [Ne]3s 2 3p 3 Strontium (Sr) 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 10 4p 6 5s 2 or [Kr]5s 2 Fluorine (F) 1s 2 2s 2 2p 5