题干

我国科学家用滤纸和二氧化钛(TiO2)薄膜制作出一种新型“纳米纸”,又在纳米纸上“铺”一层“萘胺”(C10H9N)染料,制成一种试纸,用于检测食品中亚硝酸盐浓度的高低.下列说法正确的是(   )

A:二氧化钛中Ti的化合价为+2

B:萘胺中C,H,N的质量比为10:9:1

C:二氧化钛属于氧化物

D:这种试纸是一种新型化合物

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答案(点此获取答案解析)

C

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