试题与答案

下图是实验室常用的实验仪器.请回答下列问题: (1)配制一定溶质质量分数的NaC

题型:填空题

题目:

下图是实验室常用的实验仪器.请回答下列问题:

(1)配制一定溶质质量分数的NaCl溶液时,要溶解已称好的NaCl固体,应选择的仪器是_________(填序号).

(2)进行过滤操作时,除选用上述有关仪器外,还缺少的一种实验用品是_________,仪器⑤所起的作用是_________.下列混合物的分离能直接用过滤的方法完成的是_________(填字母序号).

A、从酒精溶液中分离出酒精    B、从浑浊的河水中分离出泥沙C、从海水中分离出氯化钠

(3)实验室用高锰酸钾制氧气时,应选择的实验仪器是_________。

答案:

(1)②⑤;

(2)③④;引流;B;

(3)①③⑥⑦.

试题推荐
题型:阅读理解

It was the summer of 1965. DeLuca, then 17, visited Peter Buck, a family friend. Buck asked Deluca about his plans for the future. “I’m going to college, but I need a way to pay for it,” Deluca recalls saying. “Buck said, ‘you should open a sandwich shop.’ ”

That afternoon, they agreed to be partners. And they set a goal: to open 32 stores in ten years. After doing some research, Buck wrote a check for $ 1,000. DeLuca rented a storefront (店面) in Connecticut, and when they couldn’t cover their start-up costs, Buck kicked in another $1,000.

But business didn’t go smoothly as they expected. DeLuca says, “After six months, we were doing poorly, but we didn’t know how badly, because we didn’t have any financial controls.” All he and Buck knew was that their sales were lower than their costs.

DeLuca was managing the store and going to the University of Bridgeport at the same time. Buck was working at his day job as a nuclear physicist in New York. They’d meet Monday evenings and brainstorm ideas for keeping the business running. “We convinced ourselves to open a second store. We figured we could tell the public, ‘ We are so successful, we are opening a second store.’” And they did — in the spring of 1966. Still, it was a lot of learning by trial and error.

But the partners’ learn-as-you-go approach turned out to be their greatest strength. Every Friday, DeLuca would drive around and hand-deliver the checks to pay their suppliers. “It probably took me two and a half hours and it wasn’t necessary but as a result, the suppliers got to know me very well, and the personal relationships established really helped out,” DeLuca says.

And having a goal was also important. “There are so many problems that can get you down. You just have to keep working toward your goal,” DeLuca adds.

DeLuca ended up founding Subway Sandwich, the multi-million-dollar restaurant chain.

小题1:Deluca opened the first sandwich shop in order to _________________________.

A.support his family

B.pay for his college education

C.help his partner expand business

D.do some research小题2:Which of the following is true of Buck?

A.He put money into the sandwich business.

B.He was a professor of business administration (管理).

C.He was studying at the University of Bridgeport.

D.He rented a storefront for DeLuca.小题3:What can we learn about their first shop?

A.It stood at an unfavorable place.

B.It lowered the prices to promote sales.

C.It made no profits due to poor management.

D.It lacked control over the quality of sandwiches.小题4:They decided to open a second store because they ______________________.

A.had enough money to do it

B.had succeeded in their business

C.wished to meet the increasing demand of customers

D.wanted to make believe that they were successful小题5:What contributes most to their success according to the author?

A.Learning by trial and error.

B.Making friends with suppliers.

C.Finding a good partner.

D.Opening chain stores.

查看答案
微信公众账号搜索答案