用酒精和水浸泡蝴蝶兰花可得到紫色溶液,该溶液遇酸溶液显红色,遇碱溶液显黄色。下列

题型:选择题

问题:

用酒精和水浸泡蝴蝶兰花可得到紫色溶液,该溶液遇酸溶液显红色,遇碱溶液显黄色。下列说法不正确的是[ ]

A.该溶液可用作酸碱指示剂

B.能使该溶液显黄色的一定是碱

C.将该溶液滴入水中,溶液仍为紫色

D.将该溶液滴入白醋中,溶液会显红色

考点:酸碱指示剂
题型:选择题

根据短文判断下列句子的正确 (T) 与错误 (F)。

     Should calligraphy (书法) be taught at school?

     Although in an information age, most things can be found or done on the computer, we should go back

to handwriting by using a brush and ink. Some people think students should study calligraphy at school.

Calligraphy is part of our old culture. It dates back to early times. Traditional calligraphy is well worth

learning. The Chinese need to carry on with it. What's more, calligraphy is fine art, more than writing. Written

Chinese is well known for its beauty. For example, every stroke (笔画) of a character shows richness, feeling,

energy and so on. Even foreigners enjoy looking at it for its beauty. If you are good at it, it is certainly a way

of self-cultivation (自我陶冶). It often helps build up one's personality. Are you going to learn it soon?

( )1. Our time is called an information age.                        

( )2. Calligraphy is part of Chinese culture.                       

( )3. There is nothing in Chinese writing.                          

( )4. Only foreigners enjoy the beauty of calligraphy.              

( )5. The writer thinks that calligraphy should be taught at school.

题型:选择题

某打捞公司利用声纳测某艘沉船的位置,在海面上通过声纳向海里发出声音,经0.3秒后,接收到反射的声音。问:这艘沉船离打捞船的距离为多少米?(已知声音在海水的传播速度为1530米/秒)

题型:选择题

风险解析法,也称风险( )法。

A.结构分解

B.集中约束

C.合理规避

D.交互变更

题型:选择题

取标准状况下2.24L某气态烃置于密闭容器中,再通入足量的O2,用电火花引燃,燃烧产物的定量测定实验数据如下(图中的箭头表示气体的流向).

通过计算回答:

(1)该烃的分子式______

(2)写出可能的结构简式______,______.

题型:选择题

交流电动机空载状态下运行应记录()等有关数据,且应符合建筑设备或工艺装置的空载状态运行要求。

A.电流

B.电压

C.温度

D.转速

E.运行时间

更多题库