A. 正确 B. 错误
A. 炉管颜色变黑,脱皮出现斑点 B. 炉管表面温度偏高 C. 炉管表面氧化层增加 D. 炉管变形
A. t1/2=0.693×k B. t1/2=0.693/k C. t1/2=k/0.693 D. t1/2=0.693+k E. t1/2=0.693-k