【单选题】在滴定反应 K 2 Cr 2 O 7 + 6 FeSO 4 +H 2 SO 4 → 3 Fe 2 (SO 4 ) 3 +Cr 2 (SO 4 ) 3 +K 2 SO 4 +H 2 O 达到计量点时,下列各说法正确的是 ( )
A.
溶液中 Fe 2 (SO 4 ) 3 和 Cr 2 (SO 4 ) 3 的物质的量浓度相等
B.
溶液中 Fe 2 (SO 4 ) 3 和 Cr 2 (SO 4 ) 3 的物质的量浓度之比为1:3
【单选题】The musical comedy Oklahoma! did much to expand the potential of the musical stage, and it encouraged others to attempt ______
C.
that were original themes
【简答题】Find out the phrases "with +" "in +" when Polly was asked or replied in the passage and fill in the blanks.(把文章中的Poly问答中表示感情的带有with或 in词组找出来,并填空) in 填空1 with 填空2 in 填空3 with 填空1
【多选题】在滴定反应K 2 Cr 2 O 7 +6FeSO 4 +7H 2 SO 4 ==3Fe 2 (SO 4 ) 3 +Cr 2 (SO 4 ) 3 +K 2 SO 4 +7H 2 O达到化学计量点时,下列说法中正确的是( )。
A.
溶液中Fe 2 (SO 4 ) 3 与Cr 2 (SO 4 ) 3 的浓度(mol/L)之比为3:1
B.
溶液中Fe 2 (SO 4 ) 3 与Cr 2 (SO 4 ) 3 的浓度(mol/L)相等
C.
液中两个电对Fe 3+ /Fe 2+ 和Cr 2 O 7 2- /Cr 3+ 的电位相等
D.
溶液中两个电对Fe 3+ /Fe 2+ 和Cr 2 O 7 2- /Cr 3+ 的电位不相等
【简答题】若主机地址是19.30.80.5,网络掩码是255.255.192.0,求其子网地址和广播地址。
【简答题】请将Phrases and Expressions 部分9个短语或表达读出来并上传音频(读一遍单词即可) in collaboration 联同,合作 in disorder 混乱 first and foremost 首先也是最重要的 registration form入住登记表 check in 登记,报到 tour leader 领队 fill in 填写(表格等) national gu...