1. density at 298 K: 0.00008988 g/cm 3 melting point: 14.01 K boiling point: 20.28 K conductivity: 0.1805 Wm -1 K -1 reacts explosively with air (if sparked) forms HCl combining power: 1 colorless gas nonmetal Hydrogen, H atomic mass: 1.00 density at 298 K: 0.0001785 g/cm 3 melting point: 0.95 K boiling point: 4.22 K conductivity: 0.1513 Wm -1 K -1 reactivity: inert example compound: combining power: description: colorless gas nonmetal Helium, He atomic mass: 4.00 density at 298 K: 0.0008999 g/cm 3 melting point 24.56 K boiling point: 27.07 K conductivity: 0.0491 Wm -1 K -1 colorless gas nonmetal Neon, Ne atomic mass: 20.20 density at 298 K: 0.0017837 g/cm 3 melting point 83.80 K boiling point: 87.30 K conductivity: 0.01772 Wm -1 K -1 colorless gas nonmetal Argon, Ar atomic mass: 39.95 density at 298 K: 0.003733 g/cm 3 melting point 115.79 K boiling point: 119.93 K conductivity: 0.00943 Wm -1 K -1 colorless gas nonmetal Krypton, Kr atomic mass: 83.80 density at 298 K: 0.005887 g/cm 3 melting point 161.36 K boiling point: 165.03 K conductivity: 0.00565 Wm -1 K -1 colorless gas nonmetal Xenon, Xe atomic mass: 131.29 nonreactive

2. density at 298 K: 0.534 g/cm 3 melting point: 453.69 K boiling point: 1620.00 K conductivity: 85 Wm -1 K -1 reactivity: reacts with water forms LiCl solid combining power: 1 silvery solid metal Lithium, Li atomic mass: 6.94 density at 298 K: 0.968 g/cm 3 melting point: 370.87 K boiling point: 1156 K conductivity: 140 Wm -1 K -1 soft, silvery solid metal Sodium, Na atomic mass: 22.99 reacts vigorously with water forms NaCl solid combining power: 1 density at 298 K: 0.856 g/cm 3 melting point: 336.53 K boiling point: 1032 K conductivity: 100 Wm -1 K -1 very soft silvery solid metal Potassium, K atomic mass: 39.10 density at 298 K: 1.532 g/cm 3 melting point: 312.46 K boiling point: 961 K conductivity: 58 Wm -1 K -1 extremely soft, silvery solid metal Rubidium, Rb atomic mass: 85.47 reacts violently with water forms KCl solid combining power: 1 reacts explosively with water forms RbCl solid combining power: 1

3. density at 298 K: 1.848 g/cm 3 melting point: 1560 K boiling point: 2742 K conductivity: 190 Wm -1 K -1 does not react with water forms BeCl 2 solid combining power: 2 hard, lead-gray solid metal Beryllium, Be atomic mass: 9.01 density at 298 K: 1.738 g/cm 3 melting point: 923 K boiling point: 1363 K conductivity: 156 Wm -1 K -1 moderately hard, silvery-white solid metal Magnesium, Mg atomic mass: 24.31 reacts very slowly with water forms MgCl 2 solid combining power: 2 density at 298 K: 1.550 g/cm 3 melting point: 1115 K boiling point: 1757 K conductivity: 200 Wm -1 K -1 moderately hard, silvery-white solid metal Calcium, Ca atomic mass: 40.08 density at 298 K: 2.630 g/cm 3 melting point: 1050 K boiling point: 1655 K conductivity: 35 Wm -1 K -1 moderately soft, silvery-white solid metal Strontium, Sr atomic mass: 87.62 reacts slowly with water forms CaCl 2 solid combining power: 2 reacts vigorously with water forms SrCl 2 solid combining power: 2

4. density at 298 K: 2.460 g/cm 3 melting point: 2349 K boiling point: 4200 K conductivity: 27 Wm -1 K -1 does not react with oxygen in air forms BCl 3 solid combining power: 3 hard, black solid metalloid Boron, B atomic mass: 10.81 density at 298 K: 2.700 g/cm 3 melting point: 933.47 K boiling point: 2792 K conductivity: 235 Wm -1 K -1 moderately hard, silvery solid metal Aluminum, Al atomic mass: 26.98 does not react with oxygen in air forms AlCl 3 solid combining power: 3 density at 298 K: 5.904 g/cm 3 melting point: 302.91 K boiling point: 2477 K conductivity: 29 Wm -1 K -1 moderately soft, silvery-white solid metal Gallium, Ga atomic mass: 69.72 density at 298 K: 7.310 g/cm 3 melting point: 429.75 K boiling point: 2345 K conductivity: 82 Wm -1 K -1 moderately soft, silvery-lustrous gray solid metal Indium, In atomic mass: 114.81 does not react with oxygen in air forms GaCl 3 solid combining power: 3 reacts very slowly with oxygen in air forms InCl 3 solid combining power: 3

5. density at 298 K: 2.267 g/cm 3 melting point: 3800 K boiling point: 4300 K conductivity: 140 Wm -1 K -1 (of metalloid form) does not react with oxygen in air forms CH 4 gas combining power: 4 hard, clear colorless solid (diamond) Nonmetal or soft, black solid metalloid Carbon, C atomic mass: 12.01 density at 298 K: 2.330 g/cm 3 melting point: 1687 K boiling point: 3173 K conductivity: 150 Wm -1 K -1 moderately hard, greyish solid metalloid Silicon, Si atomic mass: 28.09 reacts very slowly with oxygen in air forms SiH 4 gas combining power: 4 density at 298 K: 5.323 g/cm 3 melting point: 1211 K boiling point: 3093 K conductivity: 60 Wm -1 K -1 moderately soft, grayish-white solid metalloid Germanium, Ge atomic mass: 72.64 density at 298 K: 7.310 g/cm 3 melting point: 505.08 K boiling point: 2875 K conductivity: 67 Wm -1 K -1 moderately soft, silvery-lustrous gray solid metal Tin, Sn atomic mass: 118.71 Reacts very slowly with oxygen in air forms GeH 4 gas combining power: 4 reacts very slowly with oxygen in air forms SnH 4 gas combining power: 4

6. density at 298 K: 0.00125 g/cm 3 melting point: 63.05 K boiling point: 77.36 K conductivity: 0.02583 Wm -1 K -1 not very reactive forms NH 3 gas combining power: 3 colorless gas nonmetal Nitrogen, N atomic mass: 14.01 density at 298 K: 1.823 g/cm 3 melting point: 317.3 K boiling point: 550 K conductivity: 0.236 Wm -1 K -1 brittle, red solid nonmetal Phosphorus, P atomic mass: 30.97 does not react with oxygen in air forms PH 3 gas combining power: 3 density at 298 K: 5.727 g/cm 3 melting point: 354 K boiling point: 887 K conductivity: 50 Wm -1 K -1 moderately soft, steel gray solid metalloid Arsenic, As atomic mass: 74.92 density at 298 K: 6.697 g/cm 3 melting point: 903.78 K boiling point: 1860 K conductivity: 24 Wm -1 K -1 moderately soft, silvery-lustrous gray solid metalloid Antimony, Sb atomic mass: 121.76 reacts very slowly with oxygen in air forms AsH 3 gas combining power: 3 reacts very slowly with oxygen in air forms SbH 3 gas combining power: 3

7. density at 298 K: 0.00143 g/cm 3 melting point: 54.80 K boiling point: 90.19 K conductivity: 0.02568 Wm -1 K -1 reacts very slowly with metals forms H 2 O liquid combining power: 2 colorless gas nonmetal Oxygen, O atomic mass: 16.00 density at 298 K: 1.960 g/cm 3 melting point: 388.36 K boiling point: 717.87 K conductivity: 0.205 Wm -1 K -1 brittle, yellow solid nonmetal Sulfur, S atomic mass: 32.07 reacts slowly with metals forms H 2 S gas combining power: 2 density at 298 K: 4.819 g/cm 3 melting point: 494 K boiling point: 958 K conductivity: 0.52 Wm -1 K -1 moderately hard, lustrous gray solid nonmetal Selenium, Se atomic mass: 78.96 density at 298 K: 6.240 g/cm 3 melting point: 722.66 K boiling point: 1261 K conductivity: 3 Wm -1 K -1 moderately hard, silvery-lustrous grey solid metalloid Tellurium, Te atomic mass: 127.60 reacts very slowly with metals forms H 2 Se gas combining power: 2 reacts very slowly with metals forms H 2 Te gas combining power: 2

8. density at 298 K: 0.00170 g/cm 3 melting point: 53.53 K boiling point: 85.03 K conductivity: 0.0277 Wm -1 K -1 pale yellow gas nonmetal Fluorine, F atomic mass: 19.00 density at 298 K: 0.00321 g/cm 3 melting point: 171.60 K boiling point: 239.11 K conductivity: 0.0089 Wm -1 K -1 yellowish-green gas nonmetal Chlorine, Cl atomic mass: 35.45 density at 298 K: 3.12 g/cm 3 melting point: 265.8 K boiling point: 332 K conductivity: 0.12 Wm -1 K -1 red-brown liquid nonmetal Bromine, Br atomic mass: 79.90 density at 298 K: 4.93 g/cm 3 melting point: 365.85 K boiling point: 457.40 K conductivity: 0.449 Wm -1 K -1 violet-dark grey lustrous solid nonmetal Iodine, I atomic mass: 126.90 reacts with metals forms HI gas combining power: 1 reacts vigorously with metals forms HBr gas combining power: 1 reacts violently with metals forms HCl gas combining power: 1 reacts explosively with metals forms HF gas combining power: 1