下列对应微粒的电子式书写正确的是( )
A．钾离子
B．氦原子He∶
C．氯离子Cl－
D．锂原子·Li∶
答案：B
钾离子:K+；氯离子：；锂原子Li·
描述何首乌药材鉴别特征的术语是（）
A、车轮纹
B、方胜纹
C、罗盘纹
D、云锦花纹
When a fire（）at the National Exhibition, at least then priceless paintings were completely destroyed.
A.broke off
B.broke out
C.broke down
D.broke up
；锂原子Li·
；锂原子Li·