When oxidation number of Cr is +Ⅳ, its oxide is usually
unstable. ( )
A: yes
B: no
unstable. ( )
A: yes
B: no
举一反三
- Nuclides<br/>with the same number of protons but different numbers of neutrons, we<br/>called them:() A: Isotope B: Isomer C: Stable nuclide D: Unstable nuclide
- —Youdon’tlikethisoilpainting,doyou?<br/>—_____,Ilikeitbetter_____Ilookatit. A: Yes;themoment B: No;as C: No;when D: Yes;themore
- Nitric oxide (NO) is highly toxic when inhaled and should not be confused with nitrous oxide (N2O), also known as ___________ gas.
- When<br/>IR is used in the Chinese Pharmacopoeia to identify drugs, samples<br/>are usually prepared by a number of methods. The following does not<br/>belong to the sample preparation method?() A: Tablet<br/>compression method B: paste<br/>method C: membrane D: solution<br/>method E: plasma method.
- All of the following are<br/>inhalational agents, which agents its MAC value is 1.77? () A: Sevoflurane B: Enflurane C: Halothane D: Isoflurane E: Nitrous oxide