——Thousands of people come to visit Qinghai Lake every year. ——That's true. It has become our _______.
A:praise
B:prince
C:pride
D:price
请从下面四种物质中选择恰当物质,用字母代码回答1﹣4题
A.小苏打;B.熟石灰;C.维生素;D.明矾.
①N2+O2 高温电击__ 2NO ②2NO+O2=2NO2 ③3NO2+H2O=2HNO3+NO ④3O2 高温电击__ 2O3下列说法中,符合化学原理的是( )
①将5g新鲜菠菜叶片剪碎放入研钵中,加入无水乙醇后直接进行研磨②将预备好的滤纸条一端剪去两角,在距这一端1cm处用钢笔画一条横线③为增强实验效果.将滤液细线画粗些④将滤纸条画有滤液细线的一端朝下,轻轻插入层析液中,让滤液细线浸入层析液中.
该同学操作有误的是( )