皮皮学，免费搜题
登录
搜题
【单选题】
有一磷酸盐溶液,可能由 Na 3 PO 4 、 Na 2 HPO 4 、 NaH 2 PO 4 或其中二者的混合物组成,今以百里酚酞为指示剂,用盐酸标准滴定溶液滴定至终点时消耗 V1mL ,再加入甲基红指示剂,继续用盐酸标准滴定溶液滴定至终点时又消耗 V 2 mL 。当 V 2 > V 1 , V 1 > 0 时,溶液的组成为()。
A.
Na 2 HPO 4 + NaH 2 PO 4
B.
Na 3 PO 4 + Na 2 HPO 4
C.
Na 2 HPO 4
D.
Na 3 PO 4 ＋ NaH 2 PO 4
拍照语音搜题，微信中搜索"皮皮学"使用
参考答案：
参考解析：
知识点：
.
..
皮皮学刷刷变学霸
举一反三
【单选题】Though he ______ well prepared before the job interview, he failed to answer some important questions.
A.
will be
B.
would be
C.
has been
D.
had been
查看完整题目与答案
【单选题】How much did the young man know about cars?
A.
He knew little about foreign cars.
B.
He knew even less than George.
C.
He had just learned something from his girlfriend.
查看完整题目与答案
【单选题】The driver insisted(坚持) he ______ the way but he ______ lost. [     ]
A.
knew; gets
B.
knew, got
C.
know, gets
D.
knows, got
查看完整题目与答案
【简答题】He knew the problem wasserious and promised to look into it _____ he reached office. A. atthat moment        B. for that moment C.immediately           D. soon
查看完整题目与答案
【简答题】利用多表查询且赋值的功能输出学号是“201507003”同学的出生日期及选修的课程号为“07003”的成绩,输出结果为“的出生日期是:1996/10/18;选课成绩是:92”的字符串。 提示:1.使用下列语句赋值(即select给变量赋值的语句可以同时将多个表中的多个字段分别指定给多个变量一次完成) select @变量名1:=字段名1, @变量名2:=字段名2, @变量名3:=字段名3,....
查看完整题目与答案
【多选题】天然药物常用的加工方法包括( )
A.
拣、洗
B.
切片、去壳
C.
蒸、煮、烫
D.
发汗
E.
加工成一定形状、干燥
查看完整题目与答案
【单选题】He posed ________ a connoisseur in traditional Chinese paintings, but actually he knew nothing about paintings.
A.
as
B.
for
C.
like
D.
by
查看完整题目与答案
【单选题】__________ ， he knew a lot．
A.
As he was young
B.
Young as he was
C.
Young was he
D.
He was young
查看完整题目与答案
【简答题】Although he knew             little about            large amount of work done in the field ,he succeeded where more well-informed experimenters failed. A ． a the                B ． the a           ...
查看完整题目与答案
【单选题】Although he knew littleabout largeamount of work done in the field ,he succeeded where more well-informed experimenters failed.
A.
a the              
B.
the a               
C.
a 不填
D.
不填 the
查看完整题目与答案
相关题目：
【单选题】Though he ______ well prepared before the job interview, he failed to answer some important questions.
A.
will be
B.
would be
C.
has been
D.
had been
查看完整题目与答案
【单选题】How much did the young man know about cars?
A.
He knew little about foreign cars.
B.
He knew even less than George.
C.
He had just learned something from his girlfriend.
查看完整题目与答案
【单选题】The driver insisted(坚持) he ______ the way but he ______ lost. [     ]
A.
knew; gets
B.
knew, got
C.
know, gets
D.
knows, got
查看完整题目与答案
【简答题】He knew the problem wasserious and promised to look into it _____ he reached office. A. atthat moment        B. for that moment C.immediately           D. soon
查看完整题目与答案
【简答题】利用多表查询且赋值的功能输出学号是“201507003”同学的出生日期及选修的课程号为“07003”的成绩,输出结果为“的出生日期是:1996/10/18;选课成绩是:92”的字符串。 提示:1.使用下列语句赋值(即select给变量赋值的语句可以同时将多个表中的多个字段分别指定给多个变量一次完成) select @变量名1:=字段名1, @变量名2:=字段名2, @变量名3:=字段名3,....
查看完整题目与答案
【多选题】天然药物常用的加工方法包括( )
A.
拣、洗
B.
切片、去壳
C.
蒸、煮、烫
D.
发汗
E.
加工成一定形状、干燥
查看完整题目与答案
【单选题】He posed ________ a connoisseur in traditional Chinese paintings, but actually he knew nothing about paintings.
A.
as
B.
for
C.
like
D.
by
查看完整题目与答案
【单选题】__________ ， he knew a lot．
A.
As he was young
B.
Young as he was
C.
Young was he
D.
He was young
查看完整题目与答案
【简答题】Although he knew             little about            large amount of work done in the field ,he succeeded where more well-informed experimenters failed. A ． a the                B ． the a           ...
查看完整题目与答案
【单选题】Although he knew littleabout largeamount of work done in the field ,he succeeded where more well-informed experimenters failed.
A.
a the              
B.
the a               
C.
a 不填
D.
不填 the
查看完整题目与答案