numbers.php

<?php
// various element numbers go here
$numbers = [
	'H' => ["mass" => 1.008],
	'He' => ["mass" => 4.002602],
	'Li' => ["mass" => 6.94],
	'Be' => ["mass" => 9.0121831],
	'B' => ["mass" => 10.81],
	'C' => ["mass" => 12.011],
	'N' => ["mass" => 14.007],
	'O' => ["mass" => 15.999],
	'F' => ["mass" => 18.998403163],
	'Ne' => ["mass" => 20.1797],
	'Na' => ["mass" => 22.98976928], 
	'Mg' => ["mass" => 24.305],
	'Al' => ["mass" => 26.9815385],
	'Si' => ["mass" => 28.085],
	'P' => ["mass" => 30.973761998],
	'S' => ["mass" => 32.06],
	'Cl' => ["mass" => 35.45],
	'Ar' => ["mass" => 39.948],
	'K' => ["mass" => 39.0983],
	'Ca' => ["mass" => 40.078],
	'Sc' => ["mass" => 44.955908],
	'Ti' => ["mass" => 47.867],
	'V' => ["mass" => 50.9415],
	'Cr' => ["mass" => 51.9961],
	'Mn' => ["mass" => 54.938044],
	'Fe' => ["mass" => 55.845],
	'Co' => ["mass" => 58.933194],
	'Ni' => ["mass" => 58.6934],
	'Cu' => ["mass" => 63.546],
	'Zn' => ["mass" => 65.38],
	'Ga' => ["mass" => 69.723],
	'Ge' => ["mass" => 72.63],
	'As' => ["mass" => 74.921595],
	'Se' => ["mass" => 78.971],
	'Br' => ["mass" => 79.904],
	'Kr' => ["mass" => 83.798],
	'Rb' => ["mass" => 85.4678],
	'Sr' => ["mass" => 87.92],
	'Y' => ["mass" => 88.90584],
	'Zr' => ["mass" => 91.224],
	'Nb' => ["mass" => 92.90637],
	'Mo' => ["mass" => 95.95],
	'Tc' => ["mass" => 98],
	'Ru' => ["mass" => 101.07],
	'Rh' => ["mass" => 102.90550], 
	'Pd' => ["mass" => 106.42],
	'Ag' => ["mass" => 107.8682],
	'Cd' => ["mass" => 112.414],
	'In' => ["mass" => 114.818],
	'Sn' => ["mass" => 118.710],
	'Sb' => ["mass" => 121.760],
	'Te' => ["mass" => 127.60],
	'I' => ["mass" => 126.90447],
	'Xe' => ["mass" => 131.293],
	'Cs' => ["mass" => 132.90545196],
	'Ba' => ["mass" => 137.327],
	'La' => ["mass" => 138.90547],
	'Ce' => ["mass" => 140.116],
	'Pr' => ["mass" => 140.90766],
	'Nd' => ["mass" => 144.242],
	'Pm' => ["mass" => 145],
	'Sm' => ["mass" => 150.36],
	'Eu' => ["mass" => 151.964],
	'Gd' => ["mass" => 157.25],
	'Tb' => ["mass" => 158.92535],
	'Dy' => ["mass" => 162.500],
	'Ho' => ["mass" => 164.93033],
	'Er' => ["mass" => 167.259],
	'Tm' => ["mass" => 168.93422],
	'Yb' => ["mass" => 173.054],
	'Lu' => ["mass" => 174.9668],
	'Hf' => ["mass" => 178.49],
	'Ta' => ["mass" => 180.94788],
	'W' => ["mass" => 183.84],
	'Re' => ["mass" => 186.207],
	'Os' => ["mass" => 190.23],
	'Ir' => ["mass" => 192.217],
	'Pt' => ["mass" => 195.084],
	'Au' => ["mass" => 196.966569],
	'Hg' => ["mass" => 200.59],
	'Tl' => ["mass" => 204.38],
	'Pb' => ["mass" => 207.2],
	'Bi' => ["mass" => 208.98040],
	'Po' => ["mass" => 209],
	'At' => ["mass" => 210],
	'Rn' => ["mass" => 222],
	'Fr' => ["mass" => 223],
	'Ra' => ["mass" => 226],
	'Ac' => ["mass" => 227],
	'Th' => ["mass" => 232.0377],
	'Pa' => ["mass" => 231.03588],
	'U' => ["mass" => 238.02891],
	'Np' => ["mass" => 237],
	'Pu' => ["mass" => 244],
	'Am' => ["mass" => 243],
	'Cm' => ["mass" => 247],
	'Bk' => ["mass" => 247],
	'Cf' => ["mass" => 251],
	'Es' => ["mass" => 252],
	'Fm' => ["mass" => 257],
	'Md' => ["mass" => 258],
	'No' => ["mass" => 259],
	'Lr' => ["mass" => 262],
	'Rf' => ["mass" => 267],
	'Db' => ["mass" => 268],
	'Sg' => ["mass" => 271],
	'Bh' => ["mass" => 272],
	'Hs' => ["mass" => 270],
	'Mt' => ["mass" => 276],
	'Ds' => ["mass" => 281],
	'Rg' => ["mass" => 280],
	'Cn' => ["mass" => 285],
	'Nh' => ["mass" => 284],
	'Fl' => ["mass" => 289],
	'Mc' => ["mass" => 288],
	'Lv' => ["mass" => 293],
	'Ts' => ["mass" => 294],
	'Og' => ["mass" => 294]
];

// programmatically assigns the atomic numbers to each element
foreach($numbers as $key => $value) {
	$atomic = array_search($key, array_keys($numbers)) + 1;
	$numbers[$key]["atomic"] = $atomic;
}