下列离子方程式正确的是（） A．过量SO2通入Ba(NO3)2溶液3SO2+2N_爱下问搜题

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问题选择题

下列离子方程式正确的是（）

A．过量SO₂通入Ba(NO₃)₂溶液3SO₂+2NO₃^-+Ba²⁺+2H₂O===3BaSO₄+2NO+4H⁺

B．1mol的Cl₂通入含1mol FeI₂的溶液中：2Fe²^＋＋2I^－＋2Cl₂＝2Fe³^＋＋4Cl^－＋I₂

C．甲醛溶液中加入足量的银氨溶液并加热：

HCHO＋2[Ag(NH₃)₂]^＋＋2OH^－HCOO^－＋NH₄^＋＋2Ag↓＋3NH₃＋H₂O

D．向硫酸铝铵矾溶液中滴加过量的氢氧化钡溶液：NH₄⁺+Al³⁺+2SO₄²^－+2Ba²⁺+5OH^－=AlO₂^－+2BaSO₄↓+NH₃·H₂O+2H₂O

答案

答案：D

A错，正确离子方程式为：3SO₂+2NO₃^-+Ba²⁺+2H₂O===BaSO₄+2NO+4H⁺+2SO₄²^—；

B错，正确离子方程式为：2I^－＋Cl₂＝2Cl^－＋I₂；C错，正确离子方程式为：HCHO＋4[Ag(NH₃)₂]^＋＋4OH^－CO₃²^—＋2NH₄^＋＋4Ag↓＋2H₂O

完形填空

When I was a little girl, I found love in a box all because of a class assignment. On a Friday night I   36  at dinner table, “My teacher said we have to bring a box, a special box, for our valentines (情人节) on Monday”.
Mother said, “We’ll see,” and she continued eating.
What did “We’ll see” mean? I had to have that box   37  my second grade Valentine’s Day would be a disaster. Maybe they didn’t love me enough to help me with my   38 .
All Saturday I waited   39  and with Sunday arriving, my concern increased, but I   40  an enquiry（询问）about the box might   41  anger or loud voice, for in my house children only asked once. More than that   42  trouble.
Late Sunday afternoon, my father called me into the kitchen. The table was covered with colorful   43  of different kinds. A (n)   44  shoebox rested on top of it.   45  flooded through me when Daddy said, “Let’s get started   46  your project.”
In the next hour my father   47  the shoebox into impressive valentine box. Colorful paper covered the ugly cardboard with red hearts   48  to what I considered all the right places. He sang while he worked. When he finished, he was so delighted that a   49 smile spread over his face. “What do you think of that?” he asked.I answered him with a hug.
But inside,   50  danced all the way to my heart. It was the first time that my father devoted so much   51  to me, for his world consisted of work only.
The holiday party arrived, and my classmates put cards, and presents into the valentine boxes. Laughter filled our classroom until dismissal time   52 .
On the way home, I held out my valentine box for the world to   53 . The love that filled it meant more to me than all the valentines inside. The valentine box became a symbol of his love that   54  through decades of other Valentine’s Days. He gave me other gifts through the years, but none   55  compared with the love I felt within the limits of the old, empty shoebox.

B．disappointedly

单项选择题

商品房预售合同登记备案，应当由（）办理。

A．房地产开发企业

B．商品房预购人

C．房地产销售代理机构

D．房地产开发企业和商品房预购人共同