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 : actinium Symbol : ac Atomic no. : 89 Melting Point (deg c) : 1051 Boiling Point (deg c) : 3198 Discoverer : debierne/giesel (1899/1902) .. More >>