NaHSO₄与NaHCO₃是两种重要的酸式盐．

（1）NaHSO₄固体溶于水显酸性，而NaHCO₃固体溶于水显碱性，请用离子方程式并配以必要的文字说明表示NaHCO₃固体溶于水显碱性的原因______

（2）常温下把l mL 0.2mol/L的NaHSO₄溶液加水稀释成2L溶液，此时溶液中由水电离产生的c（H⁺）为______．

（3）NaHSO₄和NaHCO₃两溶液混合反应的离子方程式为______．

（4）向NaHSO₄溶液中逐滴加入Ba（OH）₂溶液至呈中性，请写出发生的离子方程式______；在以上溶液中，继续滴加Ba（OH）₂溶液，此时发生的离子方程式为______．

（5）若将等体积、等物质的量浓度的NaHCO₃溶液和Ba（OH）₂溶液混合，反应的离子方程式为______．

根据句意和首字母提示填入所缺单词。

1.  He has a soccer b______.

2.  My mother and I like playing v______very much.

3.  How m______ baseballs do you have?

4.  I don't like playing soccer because it's b______.

5.  I o______ have a brother.

6.  We have 10 soccer balls, 5 basketballs, 8 volleyballs and m______ other balls.

7.  There are some tennis r______ behind the door.

8.  They play tennis c______ day.

9.  Let's play computer games. That sounds i______.

10. Do you w______ TV in the evening?