1) What is the lightest element in the universe? a) Uranium b) Hydrogen c) Carbon d) Lithium 2) Which element is needed for combustion? a) Oxygen b) Arsenic c) Sodium d) Argon 3) Which element has the symbol Al? a) Arsenic b) Aluminium c) Argon d) Adenoids 4) Which of these elements is a metal? a) Argon b) Chlorine c) Oxygen d) Magnesium 5) Which of these elements reacts violently with water? a) Selenium b) Bromine c) Potassium d) Iron

由 匿名

排行榜

视觉风格

选项

切换模板

恢复自动保存: