题目

True forgiveness is one of the most remarkable qualities a human can possess! In the fighting between two countries in the 1970s, a young man was walking from one village to the next when he was   21   by an armed guerrilla (游击队) fighter from the enemy country. The fighter   22   the young man down the hill where he was to be   23  . But a (n)   24   thing happened. The young man, who had   25   military (军事的) training, was able to disarm (解除武装) the fighter. Now, the table was   26  , and it was the fighter who was ordered down the hill. As 1．有一包固体粉末可能由NH4Cl、Na2CO3、NaCl、NaOH、Na2SO4中的一种或几种组成．为了确定其组成，某化学兴趣小组做了以下实验：已知，步骤Ⅰ中无明显现象；请回答下列问题：（1）这包固体中一定含有的物质有Na2CO3、NaCl、Na2SO4；（2）写出沉淀部分消失的化学方程式BaCO3+2HCl=BaCl2+H2O+CO2↑．（3）溶液D中一定含有的溶质是HNO3、NaNO3、Ba（NO3）2．（4）上述操作不能完全确定固体粉末的组成．兴趣小组同学思考后发现，要达到实验目的，接下来进行的操作是取样，加水溶解，加入足量的硝酸钡溶液，再滴加酚酞，观察是否变红．