假设

含有SiO2和FeS2的某种硫铁矿2克,在氧气中充分灼烧后,残留固体的质量为1.6克,如果用500吨这样的硫铁矿,能得到98%的浓硫酸多少吨?(假设生产过程中有2%的硫损失而混入炉渣).

含有SiO2和FeS2的某种硫铁矿2克,在氧气中充分灼烧后,残留固体的质量为1.6克,如果用500吨这样的硫铁矿,能得到98%的浓硫酸多少吨?(假设生产过程中有2%的硫损失而混入炉渣).

Passage 3Questions 11 to 15 are based on the following passage.  The word science is heard so often in modern times that almost everybody has some notion of its meaning. On the other hand, its definition is difficult for many people. (79) The meaning of t

Passage 3Questions 11 to 15 are based on the following passage.  The word science is heard so often in modern times that almost everybody has some notion of its meaning. On the other hand, its definit

在对一人机作业进行了45周期的观测后发现,每周期机器工时需4.2分钟,每周期工人的作业时间平均为2.3分钟,工人的评定系数为1.2(机器的评定系数为1.0)。假设放宽率为15%,试计算该项作业的定额标准时间。

在对一人机作业进行了45周期的观测后发现,每周期机器工时需4.2分钟,每周期工人的作业时间平均为2.3分钟,工人的评定系数为1.2(机器的评定系数为1.0)。假设放宽率为15%,试计算该项作业的定额标准时间。