Quizzes, tests, exercises and puzzles for English as a Second Language (ESL), English as a foreign language (EFL), Teaching EFL (TEFL), Test of EFL (TOEFL), English for speakers of other languages (ESOL), Teaching ESOL (TESOL), TOEIC.
Element
Element : argon
Symbol : ar
Atomic no. : 18
Melting Point (deg c) : -189.35
Boiling Point (deg c) : -185.85
Discoverer : rayleigh and ramsay (1894)
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