题干

科学兴趣小组在探究酸的性质时,做了如图实验:向放有少量CuO粉末的试管中加入6毫升盐酸,观察到黑色粉末很快溶解,并得到蓝绿色溶液,而向放有少量CuO粉末的试管中加入6毫升硫酸溶液,常温下无明显现象,为什么会产生这种差异呢?

【建立猜想】①两种酸溶液的pH不同.(注:pH相同,则单位体积溶液中H+数目相同)

②两种酸溶液中的____不同.

【实验过程】

实验次数

试剂

实验条件

实验现象

1

0.2克CuO粉末+6毫升pH=0的盐酸

常温

黑色粉末很快溶解,溶液呈蓝绿色

2

0.2克CuO粉末+6毫升pH=0的硫酸

常温

无明显现象

3

0.2克CuO粉末+6毫升pH=0的硫酸+0.35克NaCl

常温

黑色粉末很快溶解.溶液呈蓝绿色

4

0.2克CuO粉末+6毫升pH=0的硫酸+0.35____

常温

无明显现象

【实验结论】常温下,pH相同的盐酸和硫酸溶液于CuO反应现象出现差异的原因是由于____促进了反应的进行.

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答案(点此获取答案解析)

阴离子,克硫酸钠,氯离子

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