如图是某化肥包装袋上的部分说明：碳酸氢铵化学式：NH4HCO3_爱下问搜题

搜题请搜索小程序“爱下问搜题”

问题填空题

如图是某化肥包装袋上的部分说明：

碳酸氢铵

化学式：NH₄HCO₃

净重：50 kg

含氮量：≥16%

注意事项：密封保存

防潮防晒

……

(1)碳酸氢铵保存时的注意事项是_________________；

(2)将碳酸氢铵和氢氧化钙混合研磨就会发生反应，并可闻到刺激性气味，请写出该反应的化学方程式______________________________________________；

闻到的刺激性气味的气体是氨气，它能使湿润的红色石蕊试纸变________色。

答案

(1)放在干燥阴凉处密封保存

(2)NH₄HCO₃+Ca(OH)₂=CaCO₃↓+NH₃↑+2H₂O 蓝

碳酸氢铵受热易分解，所以要放在干燥阴凉处密封保存。碳酸氢铵和熟石灰反应生成碳酸钙、氨气和水，氨气和水反应生成碱使湿润的红色石蕊试纸变蓝色。

完形填空

Mrs Amatuli was my teacher in the fourth grade. One day at lunch time, Mrs Amatuli asked me if she could 36 my sandwiches. She explained that I could use the money to buy a   37 lunch from the cafeteria（自助餐厅）. I was   38. I never bought my lunch at the cafeteria. It was 39  expensive for my family, and I always carried my lunch and brought the bag back home to   40 again the next day.
You can understand my   41 when I had the opportunity to buy a hot lunch. Kids always  42 about the cafeteria food but I was very 43 of them.
When we 44 lunch that day, Mrs Amatuli took me aside and said she wanted to   45 why she had bought my sandwiches. I really didn’t care why,   46 it gave me a few minutes of her precious 47  so I was very quiet as she explained.
You 48 , she was a Catholic(天主教徒) and she told me that Catholics didn’t eat red meat on Fridays—they ate 49 on Fridays.
Oh, I couldn’t   50 to get home and tell my Mom that from then on I wanted fish on Fridays. 51 my Mom understood why, she gladly fixed fish for me on Fridays. From then on, every Friday I could get in 52 with the rest of the kids for a hot lunch. I didn’t care how many of the kids complained about the cafeteria food—it 53 great to me!
I realize now that Mrs Amatuli   54  have fixed herself a fish sandwich on Fridays. She bought my sandwiches because she saw a little girl who was pleased over the simple
   55 of having a hot lunch.

B．disappointed

多项选择题

扫频仪与手机相比，主要优势在于（）。

A.不需要对网络依赖；

B.需要对网络依赖；

C.不产生话费；

D.支持清频测试。