题干

下列溶液中有关微粒的物质的量浓度关系正确的是(   )

A:常温下将物质的量浓度相等的醋酸钠、醋酸两溶液等体积混合,混合后的溶液中,已知c(Na+)>c(CH3COOH),则:c(Na+)>c(CH3COO)>c(OH)>c(H+

B:NaHSO3和NaHCO3的中性混合溶液中(S和C均用R表示):C(Na+)=c(HRO3)+2c(RO32

C:常温下,物质的量浓度和体积都相等的①Na2SO3②Na2SO4③NaHSO4三种溶液中离子总数:①<②<③

D:常温下,①pH=3的HCl溶液和pH=11的氨水等体积混合液②pH=3的HCl溶液③pH=11的氨水中由水电离出的c(H):①>③>②

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答案(点此获取答案解析)

B

同类题4

    Whether you live in Seattle or the Sahara desert, the time has come to invest in a good raincoat or umbrella, a new study suggests.

    As global temperatures continue to rise, more “extreme rain” events—intense, cats-and-dogs down pours—can be expected, said the study, published Monday in the journal Nature Climate Change. And that, scientists said, means an increased flood risk, particularly for the world's driest areas. The study challenges the idea that global warming is causing dry areas to become drier and wet areas wetter.

    “In both wet and dry regions, we see these great increases in heavy precipitation(冰雹),” lead author Markus Donat, a climate scientist at the University of New South Wales, told Nature.

    Donat and his team collected data from 1951 to 2010 on extreme precipitation events from 11, 000 weather stations around the world, Nature reported.

     In that time, the number of days with“extreme precipitation” increased 1 percent to 2 percent per decade.

  “We found a strong relationship between global warming and an increase in rainfall, particularly in areas outside of the tropics,” Donat said in a statement.

  “Importantly, this research suggests we will see these extreme rainfall events increases at regional levels in dry areas, not just as an average across the globe,” Donat added.

    Peter Stott, a senior climate scientistat Met Office, told Climate Central that the study's findings are important, because more violent rainfall and flooding will “challenge our capability toadapt to a rapidly changing climate.”

    As Nature reported, the researchaligns(结盟)with a 2015 study that found global warming has led to a sharp increase in record-breaking precipitation events. Donat told Nature that his study should come as a warning to world governments.