CuI是一种不溶于水的白色固体，它可以由反应：2Cu2++4I-=2CuI↓+I2而得到。现以石墨为阴极，以Cu为阳极电解KI溶液，通电前向电解液中加入少量酚酞和淀粉溶液。电解开始不久，阴极区溶液呈红色，而阳极区溶液呈蓝色，同时有白色沉淀生成。下列说法中正确的是
A．对阳极区溶液呈蓝色的正确解释是：2I--2e-=I2，碘遇淀粉变蓝
B．对阳极区溶液呈蓝色的正确解释是：Cu-2e-=Cu2+，Cu2+显蓝色
C．阴极区溶液呈红色的原因是：2H++2e-=H2↑，使阴极附近OH-浓度增大，溶液显碱性，从而使酚酞变红
D．阴极上的电极反应式为：Cu2++2e-=Cu
答案：C
铜是阳极，所以阳极是铜失去电子，A不正确；由于铜离子能氧化碘离子，生成单质碘碘遇淀粉变蓝，B不正确；阴极是得到电子的，所以选项C正确，D不正确，答案选C。
Weather Report (8:00 a.m. December 17—8:00 a.m. December 18) Influenced by a cold front northern Xinjiang, the eastern Qinghai-Tibet Plateau, and the northern and eastern parts of Heilongjiang are expected to experience light snow today. Drizzle (小雨) is forecast for most areas of Sichuan and western coastal areas of South China. Northerly winds of force 4-6 are expected to affect western and southwestern Inner Mongolia, and most parts of Northeast China while northerly winds of force 5-7 will sweep across the Bohai Sea, the northern parts of the Yellow Sea, East China Sea, the Taiwan Straits, and the central and northern parts of the South China Sea. Weather forecast for major Chinese cities
小题1:According to the weather report, we know it doesn’t rain in many areas except ______.
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