下列物质中,属于氧化物的是
A.NaCl
B.NaOH
C.MnO 2
D.O2
答案:C
题目分析:氧化物是由两种元素组成且一种元素是氧元素的化合物,故答案选择C
Have you ever considered a trip to Shangri-la!? The British writer James Hilton described a beautiful kingdom 小题1:.where three rivers joined together, steep mountains reached to the sky, and fields of long grass covered the earth. Three mountains, Meili, Baimang and Haba, which are covered with snow, tower over the land. Below the mountain, the sunshine reflects on the many lakes, 小题2:.making them shine like diamonds against the rich countryside. Lakes, surrounded by vast grassland, look like jewels. Sheep, cows and horses feed freely on the green grass and 小题3:.forests around are home to lots of birds and animals. In this peaceful world, 小题4:. 人们与大自然和谐相处and the noise and the worry of the outside world are forgotten. Nature has provided Shangri-la with endless natural treasures, making the land a happy home for the local people. In this perfect world lived people who had discovered 小题5:.如何永葆青青.The weather changes so quickly that people say you can experience four seasons in one day. The best time to visit Shangri-la are spring and autumn when the temperature is at it mildest.
丞相是古代皇帝的重要辅臣,设置和废除这一官职的朝代是[ ]
A.隋朝和清朝
B.秦朝和明朝
C.唐朝和明朝
D.秦朝和元朝