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问题 选择题

下列说法中正确的是（　　）

A．离子化合物中只存在离子键

B．含有离子键的化合物一定是离子化合物

C．化学键只存在于化合物中

D．非金属单质一定含有共价健

答案

答案：B

选择题

给50mL液体加热，需要使用的仪器是（ ）

①试管；②烧杯；③酒精灯；④试管架；⑤石棉网；⑥铁架台（带铁圈）。

A．①③⑤

B．②③⑤

C．②③⑤⑥

D．①③⑤⑥
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单项选择题

Questions 7 to 10 are based on the following conversation. At the end of the conversation, you will be given 20 seconds to answer the questions. Now, listen to the conversation.

Which of the following is NOT true, according to the conversation you have just heard

A．Dan has kissed Tanya as he has requested.

B．Dan has been running very fast on purpose.

C．Dan has tried his best to coax a kiss out of her.

D．Dan has not been able to put a little kiss on her cheek.
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