问题
选择题
She told us her grandfather _________ for three years. [ ]
A. has died
B. had died
C. has been dead
D. had been dead
答案
答案：D
搜题请搜索小程序“爱下问搜题”
She told us her grandfather _________ for three years. [ ]
A. has died
B. had died
C. has been dead
D. had been dead
答案：D
xC (g) + D(s) ，10s时，测得A的物质的量为1.7mol，C的反应速率为0.0225mol·L—1·s—1；40s时反应恰好处于平衡状态，此时B的转化率为20%。请填写下列空白：