【单选题】X、Y是元素周期表VIIA族中的两种元素,下列叙述中能说明X的非金属性比Y强的是 [ ]
【单选题】The fossil fuel would be __________ within half a century if we made no immediate actions now.
【单选题】Which of the following is an effective way of dealing with declining fossil fuel reserves?
A.
Use energy more efficiently
C.
Increased exploration effort in finding new fossil fuel
D.
Switch completely to nuclear power
【简答题】贾宝玉佩戴的玉叫( ),史湘云佩戴的是( )。
【单选题】X、Y是元素周期表中ⅥA族的两种元素。下列叙述中能说明X的非金属性比Y强的是 [ ]
D.
Y的最高价氧化物对应的水化物的酸性比X的最高价氧化物应的水化物的酸性强
【简答题】周期信号频谱的三个基本特点是(1)________,(2)________,(3)________。
【单选题】The best title for the passage may be______.
B.
Fossil Fuel and Garbage
【单选题】The best title for the passage may be ______.
B.
Fossil Fuel and Carbage
【单选题】X、Y是元素周期表中ⅥA族的两种元素.下列叙述中能说明X的非金属性比Y强的是( )
D.
Y的最高价氧化物对应的水化物的酸性比X的最高价氧化物应的水化物的酸性强