【简答题】Only
when the rain stopped _____ again. (1.0分)A. the
match started B. does
the match start C. did
the match start D. the
match had started
【单选题】某猪场3 日龄仔猪,陆续出现腹泻症状,排出黄色浆液状稀便,含凝乳小片,部分死亡。剖检见十二指肠黏膜卡他性炎症。取病猪小肠前段内容物接种麦康凯培养基,见圆形红色菌落生长,该病猪最可能患的疫病是
【单选题】已知 lg K ZnY =16.5,并且lg a Y(H) 对应的pH值如下: pH 4 5 6 7 lg a Y(H) 8.44 6.45 4.65 3.32 若用0.02mol·L -1 EDTA滴定0.02mol·L -1 Zn 2+ 溶液,要求 pM=0.2, E t =0.1%,则滴定时...
【单选题】Only when the rain stopped _____ again.
【单选题】Only when the rain stopped _____ again.
【简答题】A.It's not raining that hard now. B.The rain has just begun. C.It only rained a little bit. D.It's raining too hard to go out.
【单选题】Only when the rain stopped _____ again.
【简答题】在25℃下,将a mol·L -1 的CH 3 COONa与0.02 mol·L -1 的盐酸等体积充分混合,反应后测得溶液pH=7,则: (1)a 0.02(填“<”、“>”或“=”); (2)c(CH 3 COO - )+ c(CH 3 COOH)= mol·L -1 ,c(CH 3 COOH)= mol·L -1 ; (3)CH 3 COOH的电离平衡常数K a = (用含a的代数式表达)。...
【单选题】在 H 3 PO 4 存在下的 HCl 溶液中,用 0.02mol·l - 1 的 K 2 Cr 2 O 7 溶液滴定 0.1mol·L - 1 的 Fe 2+ 溶液,其计量点的电位为 0.86v , 对此滴定最适宜的指示剂为:( )
【单选题】Going out for a walk when it's pouring with rain is a______idea.