题干

某小组同学进行了有关蜡烛成分测定的实验,请你帮他们完成实验报告:

实验步骤

现象

结论

在蜡烛火焰上方罩一个冷而干燥的烧杯

烧杯内壁有小液滴

产物中有____

将内壁涂有____的烧杯罩在火焰上方

____

产物中有二氧化碳

由此可知:蜡烛的成分中一定含有____,可能还含有____元素.

上一题 下一题 0.0难度 选择题 更新时间:2019-03-28 08:38:06

答案(点此获取答案解析)

水,澄清石灰水,烧杯内壁出现白色浑浊现象,碳元素和氢元素,氧

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    Xiaomi's sales strategy is largely responsible for the decline, having grown indistinguishable from that of many other Chinese manufacturers, according to Hong Kong-based cell-phone market journalist Yasuhiro Yamane. When the company first arrived on the scene in 2011 and 2012, its products were sold online by reservation only, building an air of exclusivity(排外)and lending the brand a high image. This strengthened the appeal of the smart phones, which resembled Apple's iPhones.

    But starting in 2013, Xiaomi began concentrating on high-volume sales, allowing many more resellers to carry its phones—a critical turning point in the company's fortunes. While sales increased, Xiaomi's products became viewed less as premium items and more as widely available, mass-market phones, according to Yamane.

    To keep consumers from losing interest, Xiaomi introduced a lower-end brand, Redmi, in July 2013. Phones in that family sell for 1000 yuan($150) or less, around half the price of products from the flagship Mi series.

    When China's economy began to skid at the end of 2014, the company leaned harder on the Redmi brand to hold on to market share in the following year—a grave mistake. Though it had some effect, the strategy ultimately “drove home the image of Xiaomi as a low-cost phone maker,” Yamane said.

    This should serve as a warning to other makers in China, where companies tend to emerge and quickly disappear due to their focus on short-term gains over long-term planning. “There is still a chance that Xiaomi could right itself and regain its old appeal,” Yamane said.