下列离子方程式正确的是 A.铁与稀反应:↑ B.小苏打与氢氧化钠溶液混合: C.氯化钙与碳酸氢钾溶液混合: D.溶液与溶液混合:
It was a painful 100 hours from the moment the earthquake struck until rescuers pulled Liu Deyun from the ruins of a factory yesterday. When he went to work on Monday morning, he had never thought tha
小明做“将浓硫酸滴到一小块布上”的实验,发现生成的炭上冒“白烟”,推测炭能与浓硫酸反应。欲探究其生成物成分,通过简单分析及实验确定无H2
如图7甲所示是某同学探究加速度与力的关系的实验装置。他在气垫导轨上B处安装了一个光电门,滑块上固定一遮光条,滑块用细线绕过气垫导轨左端的
下列物质中,属于氧化物的是( ) A.H2SO4 B.O2 C.K2MnO4 D.Al2O3
沈绣是清末刺绣艺术大师沈寿吸收西洋油画的光与影、明与暗的绘画理念,革新中国传统刺绣针法和色线用法而独创的一种极具艺术表现力的仿真绣技
伏尔泰说:“如果在英国仅允许有一种宗教,政府很可能会变得专横;如果只有两种宗教,人民就会互相割断对方的喉咙。”伏尔泰所要表达的观点主
When he was there, he ____ go to that coffee shop at he street corner after work every day. A. would B. should C. had better D. might