题干

关于质量守恒定律的理解,错误的是(   )

A:煤燃烧后灰渣质量小于煤,不能用质量守恒定律解释

B:宏观:实际参加反应的反应物总质量等于生成物总质量

C:微观:化学反应前后原子种类和个数不变

D:X+3H2O═2H3PO4中的X为P2O5

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A

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    Do you know what a big dream is? Does a big dream show one's future? Or, is a big dream something that provides only entertainment? Children dream big dreams, but there are three barriers to realizing dreams____

The self

    Immediately following the birth of a big dream, a negative self-talk takes over and gives all the reasons why it cannot happen. This voice inside of people is the ego(自我).It's there for protecting and should be listened to. Sometimes it is right, but more often it is wrong____ That's why only a handful of people make their dream come true

Family and friends

    Family and friends are a lot the ego.____ so they will often list all the reasons why the big dreams won't come true. Sometimes, family and friends destroy dreams of those they love most, out of their own fear of those left behind.

____

    If one gets past the first two barriers, one has to face the world. It is the last and the most terrible barrier. In the past, big dreamers were locked up and sometimes even killed when they were shown to the world. Fortunately, in most of the world today, big dreamers just get laughed at ____When children feel confident and then try their best, they will be ready to accept any failure. The truth is that every great dreamer whose dreams have never seen the light of success knows failure well. They simply fail until they succeed

A. The world

B. The future

C. Most people are influenced by it

D. They want to protect those they love

E. And their big dream is to be a rock star or a famous artist

F. They often kill them before they ever have a chance to grow

G. The way to realize a big dream is with confidence and action