易拉罐罐体经常用镁铝合金制成，取镁铝合金10g与一定质量9.8%的稀硫酸恰好完全反应，将反应后的溶液蒸发，得到不含结晶水的硫酸盐固体58g，则反应中生成氢气的质量为（ ）
A．0.5 g
B．1g
C．2g
D．无法计算
在H2SO4中，氢元素和硫酸根的质量比为：2：96，
58g硫酸盐固体中，镁元素和铝元素的质量占10g，则硫酸根的质量为：58g-10g=48g
设当硫酸根的质量为48g时，氢元素的质量为X，
则有：2：96=X：48g，
X=1g，
这1g氢元素完全转化成氢气，所以反应中生成氢气的质量为1g．
故选：B．
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| I have a friend named Monty Roberts who owns a horse ranch(牧场). He has let me use his 1 to raise money for poor students. 2 I was there he introduced me by saying,"I want to tell you why I let Jack use my house. It all goes back to a story about a boy who was the son of a 3 horse trainer. " One day the boy was 4 to write a paper about what he wanted to do when he grew up. He wrote a paper describing his 5 of someday owning a horse ranch. Two days later he 6 his paper back. On the front page was a large red "F" with a note 7 ,"See me after class. " The boy went to see the 8 after class and asked,"Why did I receive an F?"The teacher said,"This is a(n) 9 dream for a young boy like you. You have no coins. 10 a horse ranch requires a lot of 11 . "Then the teacher added,"lf you 12 rewrite this paper with a more realistic goal,I will 13 your grade. "The boy went home and 14 about it long and hard. Finally,the boy 15 the same paper,making no 16 at all. He said,"You can keep the F and I'll keep my 17 ." Having told the story,Monty said,"l tell you this story 18 you are sitting on my 200-acre horse ranch. I still have that school paper 19 ; over the fireplace. " He added, "The best part of the story is that the same teacher brought 30 kids to camp out on my ranch for a week. " When the teacher was leaving,he said, " Look,Monty,I can tell you this now. When I was your teacher,I was something of a dream 20 . Fortunately you had enough determination not to give up. " Don't let anyone steal your dreams. Follow your heart,no matter what happens. | ||||
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