问题 填空题

硫酸亚铁铵【(NH4)2Fe(SO4)2】俗称莫尔盐,工业上用途广泛,该物质属于   

A、酸      B、碱        C、盐

某同学为了验证硫酸亚铁铵晶体中的阳离子,进行了如下操作。

(1)室温下,将少量的硫酸亚铁铵晶体配成溶液,并将所配溶液分置于两支试管中,用其中一支进行验证Fe2+的实验,请完成下表:

操作①往试管中滴入几滴   溶液(填化学式)②继续滴入几滴新制氯水
现象溶液无明显变化溶液显红色
原因溶液中没有Fe3+(用简要文字说明原因)

                       

 

(2)为了验证NH4+该同学往另一支试管中滴加过量的浓氢氧化钠溶液并加热,并在试管口用湿润的红色石蕊试纸检验反应产物,红色石蕊试纸变蓝,同时试管内有红褐色固体产生,则加热时试管内反应的离子方程式是           。

答案

C (1)操作 ①KSCN  原因氯气有氧化性,将亚铁离子氧化为铁离子。铁离子遇到KSCN溶液显红色。(2)8NH4++4Fe2++16OH-+O24Fe(OH)3↓+8NH3↑+6H2O

题目分析:Fe3+的水溶液遇到SCN-时会变为红色,Fe2+遇到SCN-不变色。在实验室中常利用这一特性来检验。Fe3+的存在。但是Fe2+有强的还原性,当它和强氧化剂如氯气、过氧化氢、重铬酸钾等物质时会被氧化为Fe3+.这时就会和SCN-发生反应,溶液变为血红色。如果溶液中含有铵根离子,遇到热的碱溶液时发生反应:NH4++OH-NH3↑+H2O. 氨气的水溶液显碱性能使湿润的红色石蕊试纸变蓝色。根据硫酸亚铁铵溶液中滴加过量的浓氢氧化钠溶液并加热,并在试管口用湿润的红色石蕊试纸检验反应产物,红色石蕊试纸变蓝,同时试管内有红褐色固体产生,可知反应产物除了氨气还有氢氧化铁沉淀。结合质量守恒定律,产物还应该有水。反应的化学方程式为:8NH4++4Fe2++16OH-+O24Fe(OH)3↓+8NH3↑+6H2O4+、Fe3+、Fe2+的检验及Fe3+和Fe2+的相互转化的知识。

完形填空

Like any good mother, when Karen found out that another baby was on the way, she did what she could to help her three-year-old son, Michael, prepare for a new baby. They found out that it was going to be a girl, and day after day, night after night, Michael 21._____ to his sister in Mommy’s tummy.

The pregnancy progressed 22._____for Karen. Then the labor pains came. Every five minutes ... every minute. But complications   23.__  during delivery. Finally, Michael’s little sister was born. But she was in serious 24._____. With siren (警报)howling in the night, the ambulance 25.____ the infant to the Intensive Care unit at St. Mary’s Hospital in Knoxville, Tennessee.

26.______ inch by. The little girl got worse. The doctors told the parents, "There is very little hope. " Karen and her husband contacted a local cemetery (墓地) about a burial plot. They had 27.______ a special room in their home for the new baby — now they planned a funeral.

Week two in Intensive Care. It looked as if a funeral would come 28 _____the week was over. Michael, kept begging his parents to let him see his sister, "I want to sing to her," he said. Kids were never 29______in Intensive Care. But Karen made up her mind. She would take Michael 30._______they liked it or not.

She 31.______ him in an oversized scrub suit and 32.____ him into ICU. He looked like a walking laundry basket, but the head nurse33. _____him as a child, "Get that kid out of here now! " The usually 34._____ lady glared into the head nurse’s face, her lips a 35.____ line. "He is not leaving until he sings to his sister!" Karen towed Michael to his sister’s bedside. He gazed at the tiny baby 36.____ the battle to live. And he began to sing 37._____ the pure hearted voice of a 3-year-old, Michael sang:

"You are my sunshine, my only sunshine, you make me happy when skies are gray"

38. ______ the baby girl responded. The pulse rate became 39._____ and steady.

Keep on singing, Michael. "You never know, dear, how much I love you. Please don’t take my sunshine away — " The breathing became as smooth as a kitten’s purr.

Keep on singing, Michael. "The other night, dear, as I lay sleeping,… " Michael’s little sister relaxed as rest.

Funeral plans were 40______. The next day — the very next day — the little girl was well enough to go home!

The medical staff just called it a miracle. Karen called it a miracle of God’s love!

小题1:A. talked      B sang          C. played        D whispered

小题2: A. quietly      B peacefully     C hopefully      D normally

小题3: A. arose        B. raised       C rose           D aroused

小题4: A situation      B condition     C place          D position

小题5:A took         B sent          C carried         D rushed

小题6:A The years     B The months    C The weeks     D The days

小题7:A fixed up      B made up       C built up        D set up

小题8: A until         B before         C after          D when

小题9:A asked        B allowed        C admitted       D acquired

小题10: A no matter      B even if        C whether       D as if

小题11:A put          B dressed         C wore           D fit

小题12: A marched        B forced         C hid           D followed

小题13:A required        B replied         C recognized      D regarded

小题14: A   warm-hearted                B well-managed

C   mild-mannered               D cold-blooded

小题15: A firm           B strong       C hard           D tough

小题16: A losing         B lost          C to lose         D having lost

小题17:A in            B on           C at             D with

小题18:A Finally        B Instantly       C Patiently       D Interestingly

小题19:A calm          B quiet          C slow          D fast

小题20: A put off        B put away       C put up         D put down

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