短周期元素X、Y、Z在元素周期表中的位置如图所示，下列说法正确的是
| A．X、Y、Z三种元素中，X的非金属性最强 |
| B．Y的氢化物的稳定性比Z的弱 |
| C．X的单质的熔点比Z的低 |
| D．Y的最高正化合价为+7 |
相关试题
Now that we’ve discussed our problem, are people happy with the decisions _______? 
| A．taking | B．take | C．taken | D．to take |
Everybody was touched _____ words after they heard her moving story. 
| A．beyond | B．without | C．of | D．in |
One of the most important questions they had to consider was _____ of public health. 
| A．what | B．this |
C．that | D．which |
Encourage your children to try new things, but try not to ___ them too hard.
| A．draw | B．strike | C．rush | D．push |
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