I don't know his address, ______.
A. otherwise I will to him
B. otherwise I would write to him
C. otherwise I had written to him
D. otherwise I would have written to him
下列有关试剂存放说法错误的是( )。
A. 醚类化合物一般存放不能超过一年
B. 腐蚀性试剂宜存放在搪瓷桶中
C. 液体石蜡不需密封保存
D. 烯烃暴露在空气中易生成过氧化物而产生危险
71()
A. mouth
B. tone
C. head
D. tongue
下列不属于易爆试剂的是( )。
A. 高氯酸盐
B. 亚硝基化合物
C. 重氮化合物
D. 硫化物