Elemental Info Finder | Python Fiddle

import requests
from bs4 import BeautifulSoup

elements = dict()
elements["hydrogen"] = '1'
elements["helium"] = '2'
elements["lithium"] = '3'
elements["beryllium"] = '4'
elements["boron"] = '5'
elements["carbon"] = '6'
elements["nitrogen"] = '7'
elements["oxygen"] = '8'
elements["fluorine"] = '9'
elements["neon"] = '10'
elements["sodium"] = '11'
elements["magnesium"] = '12'
elements["aluminum"] = '13'
elements["silicon"] = '14'
elements["phosphorus"] = '15'
elements["sulfur"] = '16'
elements["chlorine"] = '17'
elements["argon"] = '18'
elements["potassium"] = '19'
elements["calcium"] = '20'
elements["scandium"] = '21'
elements["titanium"] = '22'
elements["vanadium"] = '23'
elements["chromium"] = '24'
elements["manganese"] = '25'
elements["iron"] = '26'
elements["cobalt"] = '27'
elements["nickel"] = '28'
elements["copper"] = '29'
elements["zinc"] = '30'
elements["gallium"] = '31'
elements["germanium"] = '32'
elements["arsenic"] = '33'
elements["selenium"] = '34'
elements["bromine"] = '35'
elements["krypton"] = '36'
elements["rubidium"] = '37'
elements["strontium"] = '38'
elements["yttrium"] = '39'
elements["zirconium"] = '40'
elements["niobium"] = '41'
elements["molybdenum"] = '42'
elements["technetium"] = '43'
elements["ruthenium"] = '44'
elements["rhodium"] = '45'
elements["palladium"] = '46'
elements["silver"] = '47'
elements["cadmium"] = '48'
elements["indium"] = '49'
elements["tin"] = '50'
elements["antimony"] = '51'
elements["tellurium"] = '52'
elements["iodine"] = '53'
elements["xenon"] = '54'
elements["caesium"] = '55'
elements["barium"] = '56'
elements["lanthanum"] = '57'
elements["cerium"] = '58'
elements["phraseodymium"] = '59'
elements["neodymium"] = '60'
elements["propmethium"] = '61'
elements["samarium"] = '62'
elements["europium"] = '63'
elements["gadolinium"] = '64'
elements["terbium"] = '65'
elements["dysprosium"] = '66'
elements["holmium"] = '67'
elements["erbium"] = '68'
elements["thulium"] = '69'
elements["ytterbium"] = '70'
elements["lutetium"] = '71'
elements["hafnium"] = '72'
elements["tantalum"] = '73'
elements["tungsten"] = '74'
elements["rhenium"] = '75'
elements["osmium"] = '76'
elements["iridium"] = '77'
elements["platinum"] = '78'
elements["gold"] = '79'
elements["mercury"] = '80'
elements["thallium"] = '81'
elements["lead"] = '82'
elements["bismuth"] = '83'
elements["polonium"] = '84'
elements["astatine"] = '85'
elements["radon"] = '86'
elements["francium"] = '87'
elements['radium'] = '88'
elements["actinium"] = '89'
elements["thorium"] = '90'
elements["protactinium"] = '91'
elements["uranium"] = '92'
elements["neptunium"] = '93'
elements["plutonium"] = '94'
elements["americium"] = '95'
elements["curium"] = '96'
elements["berkelium"] = '97'
elements["californium"] = '98'
elements["einsteinium"] = '99'
elements["fermium"] = '100'
elements["mendelevium"] = '101'
elements["nobelium"] = '102'
elements["lawrencium"] = '103'
elements["rutherfordium"] = '104'
elements["dubnium"] = '105'
elements["seaborgium"] = '106'
elements["bohrium"] = '107'
elements["hassium"] = '108'
elements["meitnerium"] = '109'
elements["darmstadtium"] = '110'
elements["roentgenium"] = '111'
elements["copernicium"] = '112'
elements['nihonium'] = '113'
elements['flerovium'] = '114'
elements['moscovium'] = '115'
elements['livermorium'] = '116'
elements['tennessine'] = '117'
elements['oganesson'] = '118'
while True:    
        try:
            element = (input("Name an element: ")).lower().replace(' ', '')
        except ValueError:
            print("Invalid input")
            continue        
        if element not in elements:
            print("Unknown element")
            continue
        else:
            break
meta_out = ''
messy_url = ['http://www.rsc.org/periodic-table/element/', elements[element]]
url = ''.join(messy_url)
r = requests.get(url)
soup = BeautifulSoup(r.content, 'lxml')
spans = soup.find('meta', {'name':'description'})['content']
for meta in spans:
    meta_out = meta_out + meta
final = meta_out.replace('Sources, facts, uses, scarcity (SRI), podcasts, alchemical symbols, videos and images.', '')
output = final.replace(', ', '\n')
print(output)

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