Classmate, this picture is blurred and can't be seen clearly. Try to answer you: this question examines the law of conservation of mass. According to the fact that the mass synthesis of substances before the reaction is equal to the total mass of substances after the reaction, the mass of substances A after the reaction can be found to be 1. Because the mass of substance A remains unchanged before and after the reaction, it may be a catalyst (note that it is possible, not necessarily, because it may also be a substance that does not participate in the reaction. ), B is correct. The mass of B and C increases, but the mass of D decreases, so it is a combination reaction (only the mass of one substance increases and the mass of the other substance decreases). Decomposition reaction means that the mass of one substance decreases and the mass of another substance increases. ) so c is correct. D didn't see it clearly, did it mean the mass ratio of B and D in the reaction? It should be 1: 8.
So the answer is d.
Is the mass of reaction b 29? I calculated according to 29. It's too unclear.
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