问题
选择题
X、Y是元素周期表中ⅦA族的两种元素，下列能说明X的非金属性比Y强的是 ( )。
A．电子层数：X>Y
B．气态氢化物的稳定性：HX<HY
C．酸性：HXO4>HYO4
D．能发生置换反应：Y2＋2NaX=X2＋2NaY
答案
答案：C
本题考查元素非金属性强弱的比较。A、B、D项说明Y的非金属性比X的强，错误。
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X、Y是元素周期表中ⅦA族的两种元素，下列能说明X的非金属性比Y强的是 ( )。
A．电子层数：X>Y
B．气态氢化物的稳定性：HX<HY
C．酸性：HXO4>HYO4
D．能发生置换反应：Y2＋2NaX=X2＋2NaY
答案：C
本题考查元素非金属性强弱的比较。A、B、D项说明Y的非金属性比X的强，错误。
阅读下面短文，从短文后各题所给的四个选项（A、B、C和D）中，选出可以填入空白处的最佳选项，并在答题卡上将该项涂黑。 Growing up is not always easy. When facing difficulties, courage and a spirit of independence can be more useful than crying for !That’s what Hong Zhanhui’s story of __ from boy to man with family hardships ( 艰难)tell us. Hong was born in 1982 in a poor family in Xihua County, Henan Province. When he was 11, his father became mentally（心理上） ill and one day came back with an abandoned ( 被抛弃的)baby girl. A year later, Hong‘s mother and younger brother both home because of poverty ( 贫困)and pressure ( 压力)from his ill father. The burden ( 负担)fell onto the 12-year-old’s shoulders: to treat his father’s illness, to the adopted ( 领养的)sister Chenchen, and to go on to study. Hong didn’t . Since a young age, he has worked in part-time jobs to feed his family. At the same time, he has studied at college. To take care of Chenchen, he worked hard to a room near his campus for her, and send her to school. After Hong’s story went public, people were to tears by his selflessness. Hard his life was, Hong didn’t abandon his father and the adopted , because they needed his help. With his hard –won money, he even helped other students against misfortunes ( 厄运). Today when many tend to worry more about their own happiness, Hong’s deeds us of what we usually ignore（忽略）: love and care for others. Without these, of us could survive. Hong donations ( 捐献) from others. He said he felt encouraged by kind offers, but he could his own work. Short of money to buy food, the boy climbed tall trees to get birds’ eggs for his baby sister. He walked two hours at weekends to buy different things to around his school to earn money. Through his hard life, the boy developed to rise above misfortune that made him a hero in people’s eyes. Hong’s story shows that with love and willpower, no hardship can a person but himself. So when facing difficulties, don’t ___ about bad luck. Consider what more you could do for your family and society you will find the world smiling back.
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