某课外小组欲鉴定某硫酸钠样品中是否含有亚硫酸钠,设计方案如下:取少量固体配成溶液,往溶液中滴加少量酸性KMnO4溶液,观察溶液是否褪色.如果溶液紫色褪去,说明该样品中含有亚硫酸钠. (1) 用离子方程式表示该反应原理:. (2) 图I表示100mL量筒中液面的位置,A与B,B与C刻度间相差10mL,如果刻度A为30,量筒中液体的体积是 mL.图II表示25mL滴定管中液面的位置,如果液面处的读数是a,则滴定管中液体的体积(填字母) A.You can’t judge a book by its cover,
____________.
A. as the saying goes old
B. goes as the old saying
C. as the old saying goes D.
goes as old the saying