问题
单项选择题
测定食品中的铬，样品消化可用高压消解罐，也可用电热板低温消化，消化用的酸为（）。
A．硫酸和高氯酸
B．硫酸、硝酸、高氯酸
C．过氧化氢和高氯酸
D．高氯酸
E．硫酸、硝酸
答案
参考答案：E
搜题请搜索小程序“爱下问搜题”
测定食品中的铬，样品消化可用高压消解罐，也可用电热板低温消化，消化用的酸为（）。
A．硫酸和高氯酸
B．硫酸、硝酸、高氯酸
C．过氧化氢和高氯酸
D．高氯酸
E．硫酸、硝酸
参考答案：E
| 选择方框内所给的单词并用适当形式填空。 | |
see animals, but a small cage isn't a good place for an animal to live in. Today, zoos keep animals in 3______ kinds of cages. The cages are very big and 4______. The cages look like the 5______ habitats. Zoos help to protect animals, They protect animals in the zoo and they protect animals in the 6______. How do they do this? Zoos teach people how animals live in the wild. Zoos want people to help 7______ the "wild habitats". Many plants and animals are going extinct. 8______ say that seventy-four kinds of 9______ things go extinct every day! Zoos are working together to 10______ animals from going extinct. |