搜题请搜索小程序“爱下问搜题”
问题 选择题

Mg(OH)2在水中达到溶解平衡：Mg(OH)2(s)Mg2＋＋2OH－，下列哪种情况可使Mg(OH)2(s)的量减少(　　)

A．加入MgCl2溶液

B．加入少量NaOH

C．加入NH4NO3溶液

D．加入K2S溶液

答案

答案：C

A使[Mg2＋]增大，B使[OH－]增大，均使平衡逆向移动，Mg(OH)2(s)的量增加，加入K2S溶液，S2－水解呈碱性，抑制Mg(OH)2固体溶解；加入NH4NO3，NH与OH－结合生成NH3·H2O，使[OH－]减小，平衡向右移动，促进Mg(OH)2(s)溶解。

听力题

请认真阅读下面短文，并根据各题所给首字母的提示，写出一个合适的英语单词完整、正确的形式，使短文通顺。

There are four people in my family. Every day my parents are very busy trying to make 小题1: m  ▲   in order to pay the high tuition (学费) for my brother and me. They hardly say “I love you” or send flowers to each other. Besides, my father has a bad temper (脾气). It is 小题2:e  ▲   for him to lose his temper 小题3:w  ▲   he’s very tired from the hard work. I didn’t know whether there was love between them until one spring. At that time, my father 小题4:s  ▲   got badly sick. My mother had to stay with him in the小题5:h  ▲   for a month. When they returned from the hospital, they both looked very weak as if both of them had a serious illness.

After they were back, my mother helped my father小题6:w  ▲   slowly on the country road every day in the morning and dusk. 小题7:H  ▲   , after two months my father still couldn’t walk by 小题8:h  ▲   . All of us were worried about him.

　　”Dad, how are you feeling now?” I asked him one day.

“Susan, don’t小题9:w  ▲   about me.” he said in a low voice. “I just like walking with your mom. I like this kind of life.” Reading his eyes, I know he loves my mother very much.

Once I thought love meant小题10:f  ▲   , presents and sweet kisses. But from this experience, I understand that love is inside, making life strong and warm.
查看答案
问答题

简述供应商选择的程序。
查看答案