Skills Practice Answers

Skills Practice 1 9,434,880 mL 17.8 cases 0.333 pallet a) 0.1560 m b) 4.1x1010 c) 92,000 μm d) 91,600 nm a) 2.229x107 b) 8.07x106 c) 5.41x1020 d) 1.12x107 a) 2.300021x1010 b) 3.51x10-9 a) 235,400 b) 0.000000003400

Skills Practice 2 325.2 18,000 0.0175 0.790 28,910,000 27 4.9x1012 1.86x105

Skills Practice 8 a) 21 b) Scandium (Sc) c) 22 Atoms of the same element (having the same number of protons) with a different number of neutrons. a) -2 b) sulfur c) 17 1;3 +2 30 B) ions Strontium (Sr) Symbol neutrons protons electrons atomic # mass # 56 136 𝐵 𝑎 +2 80 56 54 136 25 56 𝑀 𝑛 31 25 79 199 𝐴 𝑢 120 79 199 20 41 𝐶 𝑎 +2 21 20 18 41

Skills Practice 9 a) 74.92 amu b) Arsenic (As) a) 51.99 amu b) Chromium (Cr) The most abundant is the one with a mass of 40.00 amu. 41.996 amu

Skills Practice 10 Ground state: the normal energy level that an electron occupies. Excited state: when an electron has absorbed energy to occupy a higher energy level. 7.11x10-8 m 8.62x10-20 J 3.68x10-19 J a) 8.52x1014 Hz b) 5.65x10-19 J f=7.68x1014 Hz wavelength= 3.91x10-7 m

Skills Practice 11 There is no such thing as an f sublevel in the third energy level. Also, an f sublevel if it existed would have seven orbitals instead of four. 8 10 2 Orbitals = 9 Electrons =18 50 4p

Skills Practice 13 a. ends in: 3d b. ends in: 4d c. ends in: 4p 2) a. 1s22s22p63s23p64s23d4 b. 1s22s22p63s23p64s23d104p65s24d105p3 c. 1s22s22p63s23p64s2 3) Because of Hund’s Rule the 2p sublevel should look like: 1s 2s 2p 4) Three

Skills Practice 14 a. 5 b. 2 c. 6 d. 8 e. 7 a. 2-8-3 b. 2-6 c. 2-8-6 Column 14 or IVA a. 5 dots b. 2 dots c. 4 dots d. 7 dots

Skills Practice 15 Abbreviated electron configurations: [Ar] 4s23d104p2 [Xe] 6s2 [Ar] 4s23d104p5 [Xe]6s24f145d106p3 [Ar] 4s23d5 [Xe]6s24f145d9 Column 6 (or VIB) 5th row 3rd row Each d sublevel can hold 10 electons Each p sublevel can hold 6 electrons

Skills Practice 16 The second energy level feels a +13 charge and the outer energy level feels a +5 charge. Sulfur’s outer level of electrons feels a +6 charge pulling on it from the nucleus. Silicon’s outer level feels a weaker charge of +4 and therefore it is not pulled as close to the nucleus as sulfur’s outer level. Chlorine is lower in the periodic table which would indicate that it is larger than lithium, but it is also located further to the right which would indicate that it is smaller. a) S, Al, Mg, Na b) C, Si, Sn, Pb c) Br, Se, Ca, K d) C, B, Be, Mg, Ca e) Cl, P, Al, Ga f) Ne, O, S, Se

Skills Practice 17 1. It is relatively hard to remove the first electon. 2. a) Ca, As, Se, Br b) Bi, As, P, N c) Ga, Al, Si, S d) K, Li, C, O e) Po, Te, S, O e) In, Sn, Te, I 3. Beryllium; After its two outermost electrons are removed, the next electron would need to be removed from an inner energy level, which is much more difficult. 4. Larger atoms tend to have smaller first ionization energies because the outer electrons are farther from the nucleus. Since the electrons are farther, the force of attraction from the nucleus is less.

Skills Practice 18 Fluorine atom: 2-7; Fluorine ion: 2-8 0; all atoms have a neutral charge. +2 -2, -1, -1, +2, +1, +2, +3, -3, -2, -1, +2, +1

Skills Practice 19 Ion Symbol Formulas Names Rewrite Na2S Mg+2 AlCl3 Rb+1 Ca3P2 F-1 BaO Al+3 Names S-2 Sodium sulfide Rewrite Aluminum chloride BaS Calcium phosphide Rb3N Barium oxide LiCl +1, +2, +3, +/-4, -3, -2, -1 AlN MgBr2 Al2O3

Skills Practice 20 LiC2H3O2 Calcium oxide Na3PO4 Barium chloride Mg(OH)2 Potassium phosphate Omit Magnesium hydroxide (NH4)2S K2O Sodium acetate AlPO4 Lithium sulfate NaOH Ammonium sulfate Aluminum cyanide Beryllium chlorate

Skills Practice 21 MnF4 Nickel(II) Phosphate (NH4)3PO4 Chromium(III) hydroxide Ni(NO3)2 Barium chlorate Na3N Manganese(IV) nitride Al2(SO4)3 Copper(I) carbonate Cr(OH)3 6 Fe3(PO4)2 3 CuCl2 4 Copper(II) oxide 8 Iron(II) sulfate Ammonium sulfide

Skills Practice 22 Dinitrogen pentoxide N20 Triphosphorus heptoxide Fe(NO3)2 CCl4 Trisulfur tetrafluoride C3H7 Carbon dioxide H3PO4 Dinitrogen hexoxide NO2 Copper(II) sulfate CH2 Ammonium carbonate C6H9O Sulfur hexafluoride N2H3O2 H2O4 S2O7 N3S5 C4H3O4 CO2

Skills Practice 28

Skills Practice 29

Skills Practice 30 7.02 x 1024 molecules 1121 grams Quantity of particles needed to equal an element’s atomic mass in grams. 1180 grams 183.4 amu; 183.4 g/mol 3.32 moles 1.22 x 1024 atoms 78.6 g/mol 4655 grams 1.81 x 1024 molecules

Skills Practice 31 15.4% a- 25.8% b- 64.7% a- 53.8% b- 34.4% N2O5 N3O6 a- C3H4O b- C24H32O8 C18H27O36

Skills Practice 32 35.0 g 345 g LiNO3; 100 g Ca 117 g Na3P; 239 CaSO4 181.7 g Al(NO3)3; 142 g CaCl2 41.8 g of each product