挑战习题
1/5单选题
难度:

1.夏季到了,不少人喜饮碳酸饮料.某种碳酸饮料(不含其它酸性物质)中溶有较多的二氧化碳气体,小文同学将2-3滴紫色石蕊溶液滴入少量该碳酸饮料中,然后加热,可观察到溶液颜色的变化是
A 先变蓝后变紫
B 先变无色后变红
C 先变红后变紫
D 变红后颜色不再改变
提示1:
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提示2:
5rip5bqm5Y2H6auY5Y+v5Lul5L2/5LqM5rCn5YyW56Kz5rCU5L2T6YC45Ye644CC
正确答案:Qw==
56Kz6YW46aWu5paZ5Lit5ZCr5pyJ5LqM5rCn5YyW56Kz5LiO5rC05Y+N5bqU55Sf5oiQ55qE56Kz6YW477yM5Zug5q2k5ZGI6YW45oCn44CC5Y+v5Lul5L2/55+z6JWK6K+V5YmC5Y+Y5Li657qi6Imy77ybPGJyPuWKoOeDreWQju+8jOS6jOawp+WMlueis+mAuOWHuu+8jOWboOatpOmlruaWmeS+v+WRiOS4reaAp+S6hu+8jOefs+iViuivleWJguaBouWkjee0q+iJsuOAguaVhemAiUM=