题干

用选项中的电极、溶液和如图所示装置可组成原电池.下列现象或结论叙述正确的是(  )

选项

电极a

电极b

A溶液

B溶液

现象或结论

A

Cu

Zn

CuSO4

ZnSO4

一段时间后,a增加的质量与b减少的质量相等

B

Cu

Zn

稀硫酸

ZnSO4

溶液中阳离子经过盐桥向b极移动

C

C

C

FeCl3

KI、淀粉

混合液

b极附近溶液变蓝

D

Fe

C

NaCl

FeCl3

外电路电子转移方向:b→a

A:A  

B:B  

C:C  

D:D

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答案(点此获取答案解析)

C

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    Businesses are witnessing a difficult time, which has in turn produced influence on consumers, desire to go green. However, shoppers are still laying stress on environmental concerns.

    Two thirds of customers say that environmental considerations inform their purchases to the same degree as they did a year ago, while more than a quarter say that they are now even better aware of the environmental effect on what they buy.

    This may help to influence how shops store goods on their shelves. And the companies should still make efforts to become more environmentally friendly. Two out of three people think it is important to buy from environmentally responsible companies, with about one in seven saying that they had even decided to take their custom elsewhere if they felt a company's environmental reputation was not good enough.

    Harry Morrison, chief executive (主管) of the Carbon Trust, sympathizes: “I understand this situation where survival is very important now. But from environmental considerations, the clock is ticking—we don't have much time. In addition, cutting carbon has an immediate effect as costs drop and a medium-term benefit for the brand.”

    Larger companies have an extra motivation to look at reducing their carbon footprint, as new rules next year will require businesses to buy carbon allowances to make up for their emissions (排放). Those that have taken early action will have a head start. More than two thirds of consumers are not clear about which companies are environmentally responsible. This suggests that firms that are able to relay clearly their message to the public will be in a pole position to attract shoppers.

    The Carbon Trust believes that it can help by informing customers about the good work companies are doing. “When companies are granted (授予) the standard, they can use a logo (标识) in all their marketing which makes it clear that they are working towards cutting emissions,” Mr. Morrison said.