【简答题】往含有Cu2+、Fe3+和Mg2+(浓度均为0.1 mol/L)的溶液中加入过量铁粉,充分反应后,溶液中浓度最大的阳离子是 .
【简答题】计算e的近似值 任务描述:使用泰勒级数展开式来求自然对数的底的近似值,泰勒级数展开式如下:设N=20。 任务分析,程序中利用循环求e的值,当N为20时则退出循环。程序运行后,可以显示e的近似值2.71828。
【单选题】下列溶液中微粒的物质的量浓度关系正确的是( )
A.
在FeCl 3 溶液中加入Mg(OH) 2 固体,溶液中c(Fe 3+ )下降
B.
CH 3 COOH溶液加水稀释后,恢复至原温度,溶液中c(OH - )和Kw都增大
C.
0.1 mol/L Na 2 CO 3 溶液:c(OH - )=c(HCO 3 - )+c(H 2 CO 3 )+c(H + )
D.
常温下,向0.01 mol/L NH 4 HSO 4 溶液中滴加NaOH溶液至中性:c (Na + )>c(NH 4 + )>c(SO 4 2- )>c(OH - )=c(H + )
【单选题】Both longitude and latitude ______ in degrees, minutes and seconds.
【简答题】请用适当的词完成下面的短文,并把所缺单词填写在指定的位置上,每个空只能填写一个形式正确,意义相符的单词。 Almost everyone in the world has friends.How can we make our friendship last forever? In my opinion, it's nice to have1.____because we can talk, la...
【判断题】Formal and informal are two ways if classifying groups.
【多选题】对有机磷农药中毒性脑损伤的诊断应符合下列哪些?
B.
表现为针尖样瞳孔、大汗淋漓、腺体分泌增多,肌纤维颤动、意识障碍、呼出气体有大蒜味
【简答题】用方框中所给单词或短语的适当形式填空 happy, proud, laugh at, stay in touch, try one's best, wake up 1.They all ____________ to study hard in order to go to college one day. 2.My neighbour is moving away, but I hope tha...
【简答题】单词拼写。 l. In China, people _____ (握手) when they meet. 2. It's not polite to _____ (顺便拜访) a friend's home. 3. Don't talk to him like that. He's a child ____ (毕竟). 4. I'm gradually _____ (习惯于) the table...