题干

不同种元素的本质区别在于具有不同的(  )

A:质子数

B:中子数

C:电子数

D:质量数

上一题 下一题 0.0难度 选择题 更新时间:2016-04-11 06:30:59

答案(点此获取答案解析)

A

同类题1

阅读【甲】【乙】两段选文,完成下题。

【甲】吴广素爱人,士卒多为用者。将尉醉,广故数言欲亡,忿恚尉,令辱之,以激怒其众。尉果笞广。尉剑挺,广起,夺而杀尉。陈胜佐之,并杀两尉。召令徒属曰:“公等遇雨,皆已失期,失期当斩。藉第令毋斩,而戍死者固十六七。且壮士不死即已,死即举大名耳,王侯将相宁有种乎!”徒属皆曰:“敬受命。”乃诈称公子扶苏、项燕,从民欲也。袒右,称大楚。为坛而盟,祭以尉首。陈胜自立为将军,吴广为都尉。攻大泽乡,收而攻蕲。蕲下,乃令符离人葛婴将兵徇蕲以东。攻銍、酆、苦、柘、谯皆下之。行收兵。比至陈,车六七百乘,骑千余,卒数万人。

【乙】秦二世元年七月,陈胜等起大泽中。其九月,会稽守①通谓梁②曰:“江西皆反,此亦天亡秦之时也。吾闻先即制人,后则为人所制。吾欲发兵,使公及桓楚将。”是时桓楚亡在泽中。梁曰:“桓楚亡,人莫知其处,独籍③知之耳。”梁乃出,诫籍持剑居外待。梁复入,与守坐,曰:“请召籍,使受命召桓楚。”守曰:“诺。”梁召籍入。须臾,梁眴④籍曰:“可行矣!”于是籍遂拔剑斩守头。项梁持守头,佩其印绶。门下大惊,扰乱,籍所击杀数十百人。一府中皆慴伏,莫敢起……于是梁为会稽守,籍为裨将,徇下县。

(节选自《史记·项羽本纪》)

【注】①会稽守:会稽郡的郡守。②梁:项梁,是项羽的叔父。③籍:项籍,字羽,所以又称项羽。④眴:以目示意,使眼色。

同类题5

请认真阅读下面短文,并根据短文内容回答问题。
Dear Helen,
      Thanks for your last letter. Yes, I'm enjoying myself on my exchange program in France. It's even better than I thought it would be. I was a bit nervous before I arrived here, but there was no reason to be. My host family are really nice. They go out of their way to make me feel at home. And you wouldn't believe how quickly my French has improved! I'm very comfortable speaking French now. Although I still make lots of mistakes, it doesn't make me worried as it used to. My biggest challenge (挑战) is learning how to behave (表现) at the dinner table. As you can imagine, things are really not the same as the way they are at home. For example, you shouldn't put your bread on your plate. You should put it on the table! I thought that was very strange at first, but now I'm used to it. You shouldn't eat anything with your hands except bread, not even fruit! (You have to cut it up and eat it with a fork.) Another thing is that it is very rude to say you're full. If you don't want any more food, you should just say, “It was delicious.” Also, it's rude to put your hands in your lap. You should always keep your hands, but not your elbows (肘部), on the table. I have to say, I find it difficult to remember everything, but I'm gradually getting used to things and don't find them so strange any more.
      I'll write soon and tell you more about life in France. Hope you're having a good school year.
Yours,
Li Ying