// Copyright 2009. Dr. Christer Svensson

function atommass(element){

    switch(element){
    case "H":
        return "1.00794(7)";
        break;
    case "He":
        return "4.002602(2)";
        break;
    case "Li":
        return "6.941(2)";
        break;
    case "Be":
        return "9.012182(3)";
        break;
    case "B":
        return "10.8111(7)";
        break;
    case "C":
        return "12.0107(8)";
        break;
    case "N":
        return "14.0067(2)";
        break;
    case "O":
        return "15.9994(3)";
        break;
    case "F":
        return "18.9984032(5)";
        break;
    case "Ne":
        return "20.1797(6)";
        break;
    case "Na":
        return "22.98976928(2)";
        break;
    case "Mg":
        return "24.3050(6)";
        break;
    case "Al":
        return "26.9815386(8)";
        break;
    case "Si":
        return "28.0855(3)";
        break;
    case "P":
        return "30.973762(2)";
        break;
    case "S":
        return "32.065(5)";
        break;
    case "Cl":
        return "35.453(2)";
        break;
    case "Ar":
        return "39.948(1)";
        break;
    case "K":
        return "39.0983(1)";
        break;
    case "Ca":
        return "40.078(4)";
        break;
    case "Sc":
        return "44.955912(6)";
        break;
    case "Ti":
        return "47.867(1)";
        break;
    case "V":
        return "50.9415(1)";
        break;
    case "Cr":
        return "51.9961(6)";
        break;
    case "Mn":
        return "54.938045(5)";
        break;
    case "Fe":
        return "55.845(2)";
        break;
    case "Co":
        return "58.933195(5)";
        break;
    case "Ni":
        return "58.6934(4)";
        break;
    case "Cu":
        return "63.546(3)";
        break;
    case "Zn":
        return "65.38(2)";
        break;
    case "Ga":
        return "69.723(1)";
        break;
    case "Ge":
        return "72.64(1)";
        break;
    case "As":
        return "74.92160(2)";
        break;
    case "Se":
        return "78.96(3)";
        break;
    case "Br":
        return "79.904(1)";
        break;
    case "Kr":
        return "83.798(2)";
        break;
    case "Rb":
        return "85.4678(3)";
        break;
    case "Sr":
        return "87.62(1)";
        break;
    case "Y":
        return "88.90585(2)";
        break;
    case "Zr":
        return "91.224(2)";
        break;
    case "Nb":
        return "92.90638(2)";
        break;
    case "Mo":
        return "95.96(2)";
        break;
    case "Tc":
        return "97.9072(9)";
        break; // long-life isotope
    case "Ru":
        return "101.07(2)";
        break;
    case "Rh":
        return "102.90550(2)";
        break;
    case "Pd":
        return "106.42(1)";
        break;
    case "Ag":
        return "107.8682(2)";
        break;
    case "Cd":
        return "112.411(8)";
        break;
    case "In":
        return "114.818(3)";
        break;
    case "Sn":
        return "118.710(7)";
        break;
    case "Sb":
        return "121.760(1)";
        break;
    case "Te":
        return "127.60(3)";
        break;
    case "I":
        return "126.90447(3)";
        break;
    case "Xe":
        return "131.293(6)";
        break;
    case "Cs":
        return "132.9054519(2)";
        break;
    case "Ba":
        return "137.327(7)";
        break;
    case "La":
        return "138.90547(7)";
        break;
    case "Ce":
        return "140.116(1)";
        break;
    case "Pr":
        return "140.90765(2)";
        break;
    case "Nd":
        return "144.242(3)";
        break;
    case "Pm":
        return "146.9151(9)";
        break; // long-life isotope
    case "Sm":
        return "150.36(2)";
        break;
    case "Eu":
        return "151.964(1)";
        break;
    case "Gd":
        return "157.25(3)";
        break;
    case "Tb":
        return "158.92535(2)";
        break;
    case "Dy":
        return "162.500(1)";
        break;
    case "Ho":
        return "164.93032(2)";
        break;
    case "Er":
        return "167.259(3)";
        break;
    case "Tm":
        return "168.93421(2)";
        break;
    case "Yb":
        return "173.054(5)";
        break;
    case "Lu":
        return "174.9668(1)";
        break;
    case "Hf":
        return "178.49(2)";
        break;
    case "Ta":
        return "180.94788(2)";
        break;
    case "W":
        return "183.84(1)";
        break;
    case "Re":
        return "186.207(1)";
        break;
    case "Os":
        return "190.23(3)";
        break;
    case "Ir":
        return "192.217(3)";
        break;
    case "Pt":
        return "195.084(9)";
        break;
    case "Au":
        return "196.966569(4)";
        break;
    case "Hg":
        return "200.59(2)";
        break;
    case "Tl":
        return "204.3833(2)";
        break;
    case "Pb":
        return "207.2(1)";
        break;
    case "Bi":
        return "208.98040(1)";
        break;
    case "Po":
        return "208.9824(9)";
        break; // long-life isotope
    case "At":
        return "209.9871(9)";
        break; // long-life isotope
    case "Rn":
        return "222.0176(9)";
        break; // long-life isotope
    case "Fr":
        return "223.0197(9)";
        break; // long-life isotope
    case "Ra":
        return "226.0254(9)";
        break; // long-life isotope
    case "Ac":
        return "227.0277(9)";
        break; // long-life isotope
    case "Th":
        return "232.03806(2)";
        break;
    case "Pa":
        return "231.03588(2)";
        break;
    case "U":
        return "238.02891(3)";
        break;
    case "Np":
        return "237.0482(9)";
        break; // long-life isotope
    case "Pu":
        return "244.0642(9)";
        break; // long-life isotope
    case "Am":
        return "243.0614(9)";
        break; // long-life isotope
    case "Cm":
        return "247.0703(9)";
        break; // long-life isotope
    case "Bk":
        return "247.0703(9)";
        break; // long-life isotope
    case "Cf":
        return "251.0796(9)";
        break; // long-life isotope
    case "Es":
        return "252.0830(9)";
        break; // long-life isotope
    case "Fm":
        return "257.0951(9)";
        break; // long-life isotope
    case "Md":
        return "258.0984(9)";
        break; // long-life isotope
    case "No":
        return "259.1011(9)";
        break; // long-life isotope
    case "Lr":
        return "262.110(9)";
        break; // long-life isotope
    case "Rf":
        return "261.1089(9)";
        break; // long-life isotope
    case "Db":
        return "262.1144(9)";
        break; // long-life isotope
    case "Sg":
        return "263.1186(9)";
        break; // long-life isotope
    case "Bh":
        return "264.12(9)";
        break; // long-life isotope
    case "Hs":
        return "265.1306(9)";
        break; // long-life isotope
    default:
        alert(element + " is not found in this table of elements!");
        break;
    }
}