请按氮元素的化合价由低到高将下列物质排序．
①NO2②NO③NH3④HNO3（硝酸）⑤NaNO2（亚硝酸钠）⑥N2______（填序号）．
①设二氧化氮中氮元素的化合价为x．
x+（-2）×2=0
x=+4
②设一氧化氮中氮元素的化合价为y．
y+（-2）=0
y=+2
③设氨气中氮元素的化合价为z．
z+（+1）×3=0
z=-3
④设硝酸中氮元素的化合价为w．
（+1）+w+（-2）×3=0
w=+5
⑤设亚硝酸钠中氮元素的化合价为m．
（+1）+m+（-2）×2=0
m=+3
⑥单质中元素的化合价为零．氮气为单质，因此氮气中氮元素的化合价为零．
因此六种物质中氮元素的化合价由低到高的顺序为③⑥②⑤①④．
故答案为：③⑥②⑤①④
| 阅读填空。 | |
2______ in winter and hot in summer. 3______ in Hainan island (岛), the weather is very warm in winter and also very hot in 4______. Kunming is a spring city (春城). The weather is warm 5______ the time. In London, the weather changes very often. You can see a sunny day in the morning, and then a rainy or a cloudy day one or two 6______ later. People often talk 7______ the weather in London. They often 8______ to you,"If you don't like the weather, it doesn't matter. You can just 9______! It will change in a minute." Now people can do many things about weather. It's called man-made (人造的) weather. We 10______ one day we can decide (决定) the weather. |