问题
多项选择题
下列物质中属于弱酸的物质是（）。
A.HCL
B.HNO3
C.H2CO3
D.HAC
答案
参考答案：C, D
搜题请搜索小程序“爱下问搜题”
下列物质中属于弱酸的物质是（）。
A.HCL
B.HNO3
C.H2CO3
D.HAC
参考答案：C, D
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| Azure Warrenfeltz, a 4-year-old girl, is fluent in Japanese and Spanish. She also can 1 bits of French, German, Arabic and Italian, and she soon hopes to learn some Mandarin Chinese. In today's globalized world, Azure is one of many young American children whose parents insist her 2 include foreign languages. "It's such a 3 environment now, you never know what you might need," says Azure's mother, Julie Warrenfeltz, who started schooling her daughter in foreign languages when she was 6 weeks old. "She couldn't 4 a violin, she couldn't stand upright, but I wanted her to do 5 ." Not only is learning a foreign language easier for children than it is for 6 , but children who are exposed to other languages also do better in school. They are more 7 to diversity, says Fran?ois Thibaut, who runs The Language Workshop for Children, which has nine schools around the East Coast. Language study for children is based on immersion (沉浸), he says. Kids sing songs and play games to help develop language comprehension skills. When children start learning languages at birth, they have the 8 to learn many languages at once without getting 9 -because, as the brain develops, so too does the ability to separate one 10 from another. | ||||
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任意
比例混合的氮气和氧气所含的原子数为NA ④在标准状况下，22.4LSO3的物质的量为1mol ⑤4℃时5.4mL的水所含的原子总数为0.9NA ⑥0.1molOH－含0.1NA个电子 ⑦1mol Na2O2与水完全反应时转移电子数为2NA