问题 填空题

NaCl溶液中混有Na2SO4、CaCl2溶液和淀粉胶体,选择适当的试剂和方法从中提纯出NaCl晶体。相应的实验过程如下:

(1)写出上述实验过程中所用试剂(写化学式):

试剂①_______________________;试剂③________________________。

(2)判断试剂①已过量的方法是:________________________________________。

(3)用化学方程式表示加入试剂②的作用:

                                                                          

(4)操作①是利用半透膜进行分离提纯。

操作①的实验结果:淀粉        (填“能”或“不能”)透过半透膜;

SO42-         (填“能”或“不能”)透过半透膜;

请用实验证明上述结果,完成下表(可不填满,也可增加):

限选试剂:1mol/L AgNO3溶液、1mol/L BaCl2溶液、1mol/L Ba(NO3)2溶液、

碘水、稀盐酸、稀硝酸

编号实验操作预期现象和结论
  
  
   
 

答案

(1)BaCl2(2分);HCl(2分)(2)静置,向上层清液中滴加少量氯化钡溶液,没有白色沉淀产生,说明氯化钡溶液已过量。(2分)

(3)BaCl2+Na2CO3=2NaCl+BaCO3↓     CaCl2+Na2CO3=2NaCl+CaCO3↓(每方程式2分,共4分))

(4)不能(1分); 能(1分); 填表(共8分)

 

编号

实验操作预期现象和结论
取半透膜外液体,加入少量碘水(2分)液体没有变成蓝色,证明淀粉不能透过半透膜(2分)
另取半透膜外液体,加入足量稀盐酸和少量1mol/L BaCl2溶液(2分)产生不溶于盐酸的白色沉淀,证明SO42-能够透过半透膜(2分)

题目分析:根据题给流程图分析:混合液先通过渗析分离出淀粉胶体,再向剩余溶液中加过量氯化钡溶液,         除去硫酸根,然后再加过量的碳酸钠溶液除去钙离子和过量的钡离子,过滤后向滤液中加适量盐酸,除去过量的碳酸钠,蒸发的氯化钠晶体。(1)根据上述分析知,试剂①为BaCl2;试剂③HCl。(2)判断氯化钡溶液已过量的方法是:静置,向上层清液中滴加少量氯化钡溶液,没有白色沉淀产生,说明氯化钡溶液已过量。(3)加过量的碳酸钠溶液目的是除去钙离子和过量的钡离子,反应的化学方程式为  BaCl2+Na2CO3=2NaCl+BaCO3↓     CaCl2+Na2CO3=2NaCl+CaCO3↓。(4)利用溶液中小的分子或离子能透过半透膜,胶体微粒不能透过半透膜,采用渗析的方法将二者分离,然后再分别用碘单质检验淀粉,用盐酸和氯化钡溶液检验硫酸根;实验方案见答案。

阅读理解

C

James Blunt is one of the most popular singers in the UK. His first album, Back to Bedlam, and his number one hit, You’re Beautiful, brought him fame in 2005. his music is a mix of pop, rock and folk.

Blunt comes to China for the first time this month, he will hold two concerts, one in Beijing and one in Shanghai on April 18 and 19 respectively.

Blunt, 34, took an unusual path to stardom. His father was a soldier and so was his grandfather.

“The only music he heard growing up was Happy Birthday and Silent Night. His father considered all music, even classical, to be unnecessary noise,’ reads Blunt’s official website.

Even though Blunt did not want to join the military, he eventually followed his father’s wishes, and served as a soldier in Kosovo on peacekeeping duty.

“Like any parents, mine wanted me to have a secure job with a regular wage and career prospects,” Blunt said. “And the one job my father knew of, that he’d had experience of himself, was the army, so he could help me in that direction.”

Blunt eventually became a Captain. One of his final duties in the army before retirement was carrying the coffin(棺材) at the funeral of the Queen Mother of England in 2002.

But Blunt couldn’t escape his love for music. So, after leaving the British Army he moved to Los Angeles and worked on his first album. While in LA, Blunt lived with the actress Carrie Fisher, who played the lead female role in the Star Wars movie. He recorded his song, Goodbye My Lover, in his bathroom, where he kept a piano.

Blunt took his new album back to England where it was not very successful. But he kept performing and eventually his song, Youre Beautiful, became a number one hit.

Now Blunt has won numerous awards, sold millions of records and dated super models.

But his greatest accomplishment might be that his father now enjoys music!

59. All of the following belongs to Blunt EXCEPT__________.

A. Back to Bedlam                 B. Silent Night     

C. Goodbye My Lover              D. You’re Beautiful

60. Which of the following proves “Blunt took an unusual path to stardom”?

A. Blunt was 34 when be became famous.

B. Blunt recorded his most famous song in a bathroom.

C. Blunt’s father wanted him to have a secure job.

D. Blunt began to pursue a career in music after military service.

61. We can infer from the passage that __________.

A. Blunt is living in Los Angeles at present

B. Blunt rose to fame two years after he left the army

C. Blunt became successful immediately he recorded his first song

D. Blunt has changed his father’s attitude towards music

62. What is the passage mainly about?

A. Blunt’s visit to China              B. Blunt’s military life.

C. How Blunt became famous          D. How Blunt father fell in love with music.

多项选择题