【单选题】I was born in Tuckahoe, Talbot Country, Maryland. I have no accurate knowledge of my age, never having seen any authentic record containing it. By far the larger part of the slaves know as little of t...
【简答题】完形填空。 I'm twelve years old. I'm large 1 my age and have big feet. I look like both my mum and my dad but in 2 ways. I have fair hair and blue eyes 3 my dad, and a mouth and expression like my mum. My ...
【简答题】向 80 mL 浓硫酸中加入 g 铜片,加热一段时间后,至不再反应为止,计算: (1) 实验测得反应有 11.2 L 标准状况下的 SO 2 生成,被还原的硫酸的物质的量为 ______mol ,参加反应的 Cu 质量为 ______ g 。 (2) 将反应后的混合物加水稀释到 100mL 并除去不溶物,加入足量铁反应放出标准状况下 6.272 L 氢气,则原浓硫酸的物质的量浓度为 __...