【单选题】钢水定氧是以下列哪种物质作为电解质的()
【判断题】中国有“五岳归来不看山,黄山归来不看岳”的说法。()
【单选题】How much is spent on development every year ?
A.
About 3-4% of the gross sales.
B.
About 10% of the gross sales.
C.
About 8% to 10% of the gross sales.
【单选题】How much is spent on new prodoct development every year?
A.
About 8% of the gross sales.
B.
About 10% of the gross sales.
C.
About 8% to 10% of the gross sales.
【单选题】- Moo, moo! What’s it? - It’s a ____.
【单选题】工业上冶炼金属钼的化学原理为: ①2MoS 2 +7O 2 2MoO 3 +4SO 2 ; ②MoO 3 +2NH 3 ·H 2 O===(NH 4 ) 2 MoO 4 +H 2 O; ③(NH 4 ) 2 MoO 4 +2HCl===H 2 MoO 4 ↓+2NH 4 Cl; ④H 2 MoO 4 MoO 3 +H 2 O; ⑤用还原剂将MoO 3 还原成金属钼。 则下列说法正确的是
A.
上述①、③、⑤属于氧化还原反应,②、④属于非氧化还原反应
D.
利用H 2 、CO和Al分别还原等量的MoO 3 ,所消耗还原剂的物质的量之比为3∶3∶2
【判断题】中国有“五岳归来不看岳,黄山归来不看山”的说法。
【单选题】How much is spent on new product development every year?
A.
about 8% of the gross sales
B.
about 10% of the gross sales
C.
about 8% to 10% of the gross sales